How to Write a Conclusion for Research Papers (with Examples)
The conclusion of a research paper is a crucial section that plays a significant role in the overall impact and effectiveness of your research paper. However, this is also the section that typically receives less attention compared to the introduction and the body of the paper. The conclusion serves to provide a concise summary of the key findings, their significance, their implications, and a sense of closure to the study. Discussing how can the findings be applied in real-world scenarios or inform policy, practice, or decision-making is especially valuable to practitioners and policymakers. The research paper conclusion also provides researchers with clear insights and valuable information for their own work, which they can then build on and contribute to the advancement of knowledge in the field.
The research paper conclusion should explain the significance of your findings within the broader context of your field. It restates how your results contribute to the existing body of knowledge and whether they confirm or challenge existing theories or hypotheses. Also, by identifying unanswered questions or areas requiring further investigation, your awareness of the broader research landscape can be demonstrated.
Remember to tailor the research paper conclusion to the specific needs and interests of your intended audience, which may include researchers, practitioners, policymakers, or a combination of these.
Table of Contents
What is a conclusion in a research paper, summarizing conclusion, editorial conclusion, externalizing conclusion, importance of a good research paper conclusion, how to write a conclusion for your research paper, research paper conclusion examples, frequently asked questions.
A conclusion in a research paper is the final section where you summarize and wrap up your research, presenting the key findings and insights derived from your study. The research paper conclusion is not the place to introduce new information or data that was not discussed in the main body of the paper. When working on how to conclude a research paper, remember to stick to summarizing and interpreting existing content. The research paper conclusion serves the following purposes: 1
- Warn readers of the possible consequences of not attending to the problem.
- Recommend specific course(s) of action.
- Restate key ideas to drive home the ultimate point of your research paper.
- Provide a “take-home” message that you want the readers to remember about your study.
Types of conclusions for research papers
In research papers, the conclusion provides closure to the reader. The type of research paper conclusion you choose depends on the nature of your study, your goals, and your target audience. I provide you with three common types of conclusions:
A summarizing conclusion is the most common type of conclusion in research papers. It involves summarizing the main points, reiterating the research question, and restating the significance of the findings. This common type of research paper conclusion is used across different disciplines.
An editorial conclusion is less common but can be used in research papers that are focused on proposing or advocating for a particular viewpoint or policy. It involves presenting a strong editorial or opinion based on the research findings and offering recommendations or calls to action.
An externalizing conclusion is a type of conclusion that extends the research beyond the scope of the paper by suggesting potential future research directions or discussing the broader implications of the findings. This type of conclusion is often used in more theoretical or exploratory research papers.
The conclusion in a research paper serves several important purposes:
- Offers Implications and Recommendations : Your research paper conclusion is an excellent place to discuss the broader implications of your research and suggest potential areas for further study. It’s also an opportunity to offer practical recommendations based on your findings.
- Provides Closure : A good research paper conclusion provides a sense of closure to your paper. It should leave the reader with a feeling that they have reached the end of a well-structured and thought-provoking research project.
- Leaves a Lasting Impression : Writing a well-crafted research paper conclusion leaves a lasting impression on your readers. It’s your final opportunity to leave them with a new idea, a call to action, or a memorable quote.
Writing a strong conclusion for your research paper is essential to leave a lasting impression on your readers. Here’s a step-by-step process to help you create and know what to put in the conclusion of a research paper: 2
- Research Statement : Begin your research paper conclusion by restating your research statement. This reminds the reader of the main point you’ve been trying to prove throughout your paper. Keep it concise and clear.
- Key Points : Summarize the main arguments and key points you’ve made in your paper. Avoid introducing new information in the research paper conclusion. Instead, provide a concise overview of what you’ve discussed in the body of your paper.
- Address the Research Questions : If your research paper is based on specific research questions or hypotheses, briefly address whether you’ve answered them or achieved your research goals. Discuss the significance of your findings in this context.
- Significance : Highlight the importance of your research and its relevance in the broader context. Explain why your findings matter and how they contribute to the existing knowledge in your field.
- Implications : Explore the practical or theoretical implications of your research. How might your findings impact future research, policy, or real-world applications? Consider the “so what?” question.
- Future Research : Offer suggestions for future research in your area. What questions or aspects remain unanswered or warrant further investigation? This shows that your work opens the door for future exploration.
- Closing Thought : Conclude your research paper conclusion with a thought-provoking or memorable statement. This can leave a lasting impression on your readers and wrap up your paper effectively. Avoid introducing new information or arguments here.
- Proofread and Revise : Carefully proofread your conclusion for grammar, spelling, and clarity. Ensure that your ideas flow smoothly and that your conclusion is coherent and well-structured.
Remember that a well-crafted research paper conclusion is a reflection of the strength of your research and your ability to communicate its significance effectively. It should leave a lasting impression on your readers and tie together all the threads of your paper. Now you know how to start the conclusion of a research paper and what elements to include to make it impactful, let’s look at a research paper conclusion sample.
The research paper conclusion is a crucial part of your paper as it provides the final opportunity to leave a strong impression on your readers. In the research paper conclusion, summarize the main points of your research paper by restating your research statement, highlighting the most important findings, addressing the research questions or objectives, explaining the broader context of the study, discussing the significance of your findings, providing recommendations if applicable, and emphasizing the takeaway message. The main purpose of the conclusion is to remind the reader of the main point or argument of your paper and to provide a clear and concise summary of the key findings and their implications. All these elements should feature on your list of what to put in the conclusion of a research paper to create a strong final statement for your work.
A strong conclusion is a critical component of a research paper, as it provides an opportunity to wrap up your arguments, reiterate your main points, and leave a lasting impression on your readers. Here are the key elements of a strong research paper conclusion: 1. Conciseness : A research paper conclusion should be concise and to the point. It should not introduce new information or ideas that were not discussed in the body of the paper. 2. Summarization : The research paper conclusion should be comprehensive enough to give the reader a clear understanding of the research’s main contributions. 3 . Relevance : Ensure that the information included in the research paper conclusion is directly relevant to the research paper’s main topic and objectives; avoid unnecessary details. 4 . Connection to the Introduction : A well-structured research paper conclusion often revisits the key points made in the introduction and shows how the research has addressed the initial questions or objectives. 5. Emphasis : Highlight the significance and implications of your research. Why is your study important? What are the broader implications or applications of your findings? 6 . Call to Action : Include a call to action or a recommendation for future research or action based on your findings.
The length of a research paper conclusion can vary depending on several factors, including the overall length of the paper, the complexity of the research, and the specific journal requirements. While there is no strict rule for the length of a conclusion, but it’s generally advisable to keep it relatively short. A typical research paper conclusion might be around 5-10% of the paper’s total length. For example, if your paper is 10 pages long, the conclusion might be roughly half a page to one page in length.
In general, you do not need to include citations in the research paper conclusion. Citations are typically reserved for the body of the paper to support your arguments and provide evidence for your claims. However, there may be some exceptions to this rule: 1. If you are drawing a direct quote or paraphrasing a specific source in your research paper conclusion, you should include a citation to give proper credit to the original author. 2. If your conclusion refers to or discusses specific research, data, or sources that are crucial to the overall argument, citations can be included to reinforce your conclusion’s validity.
The conclusion of a research paper serves several important purposes: 1. Summarize the Key Points 2. Reinforce the Main Argument 3. Provide Closure 4. Offer Insights or Implications 5. Engage the Reader. 6. Reflect on Limitations
Remember that the primary purpose of the research paper conclusion is to leave a lasting impression on the reader, reinforcing the key points and providing closure to your research. It’s often the last part of the paper that the reader will see, so it should be strong and well-crafted.
- Makar, G., Foltz, C., Lendner, M., & Vaccaro, A. R. (2018). How to write effective discussion and conclusion sections. Clinical spine surgery, 31(8), 345-346.
- Bunton, D. (2005). The structure of PhD conclusion chapters. Journal of English for academic purposes , 4 (3), 207-224.
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Writing the parts of scientific reports
22 Writing the conclusion & recommendations
There are probably some overlaps between the Conclusion and the Discussion section. Nevertheless, this section gives you the opportunity to highlight the most important points in your report, and is sometimes the only section read. Think about what your research/ study has achieved, and the most important findings and ideas you want the reader to know. As all studies have limitations also think about what you were not able to cover (this shows that you are able to evaluate your own work objectively).
Possible structure of this section:
Use present perfect to sum up/ evaluate:
This study has explored/ has attempted …
Use past tense to state what your aim was and to refer to actions you carried out:
- This study was intended to analyse …
- The aim of this study was to …
Use present tense to evaluate your study and to state the generalizations and implications that you draw from your findings.
- The results add to the knowledge of …
- These findings s uggest that …
You can either use present tense or past tense to summarize your results.
- The findings reveal …
- It was found that …
Achievements of this study (positive)
- This study provides evidence that …
- This work has contributed to a number of key issues in the field such as …
Limitations of the study (negative)
- Several limitations should be noted. First …
Combine positive and negative remarks to give a balanced assessment:
- Although this research is somewhat limited in scope, its findings can provide a basis for future studies.
- Despite the limitations, findings from the present study can help us understand …
Use more cautious language (modal verbs may, can, could)
- There are a number of possible extensions of this research …
- The findings suggest the possibility for future research on …
- These results may be important for future studies on …
- Examining a wider context could/ would lead …
Or indicate that future research is needed
- There is still a need for future research to determine …
- Further studies should be undertaken to discover…
- It would be worthwhile to investigate …
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How to Write a Thesis or Dissertation Conclusion
Published on September 6, 2022 by Tegan George and Shona McCombes. Revised on November 20, 2023.
The conclusion is the very last part of your thesis or dissertation . It should be concise and engaging, leaving your reader with a clear understanding of your main findings, as well as the answer to your research question .
In it, you should:
- Clearly state the answer to your main research question
- Summarize and reflect on your research process
- Make recommendations for future work on your thesis or dissertation topic
- Show what new knowledge you have contributed to your field
- Wrap up your thesis or dissertation
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Table of contents
Discussion vs. conclusion, how long should your conclusion be, step 1: answer your research question, step 2: summarize and reflect on your research, step 3: make future recommendations, step 4: emphasize your contributions to your field, step 5: wrap up your thesis or dissertation, full conclusion example, conclusion checklist, other interesting articles, frequently asked questions about conclusion sections.
While your conclusion contains similar elements to your discussion section , they are not the same thing.
Your conclusion should be shorter and more general than your discussion. Instead of repeating literature from your literature review , discussing specific research results , or interpreting your data in detail, concentrate on making broad statements that sum up the most important insights of your research.
As a rule of thumb, your conclusion should not introduce new data, interpretations, or arguments.
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Depending on whether you are writing a thesis or dissertation, your length will vary. Generally, a conclusion should make up around 5–7% of your overall word count.
An empirical scientific study will often have a short conclusion, concisely stating the main findings and recommendations for future research. A humanities dissertation topic or systematic review , on the other hand, might require more space to conclude its analysis, tying all the previous sections together in an overall argument.
Your conclusion should begin with the main question that your thesis or dissertation aimed to address. This is your final chance to show that you’ve done what you set out to do, so make sure to formulate a clear, concise answer.
- Don’t repeat a list of all the results that you already discussed
- Do synthesize them into a final takeaway that the reader will remember.
An empirical thesis or dissertation conclusion may begin like this:
A case study –based thesis or dissertation conclusion may begin like this:
In the second example, the research aim is not directly restated, but rather added implicitly to the statement. To avoid repeating yourself, it is helpful to reformulate your aims and questions into an overall statement of what you did and how you did it.
Your conclusion is an opportunity to remind your reader why you took the approach you did, what you expected to find, and how well the results matched your expectations.
To avoid repetition , consider writing more reflectively here, rather than just writing a summary of each preceding section. Consider mentioning the effectiveness of your methodology , or perhaps any new questions or unexpected insights that arose in the process.
You can also mention any limitations of your research, but only if you haven’t already included these in the discussion. Don’t dwell on them at length, though—focus on the positives of your work.
- While x limits the generalizability of the results, this approach provides new insight into y .
- This research clearly illustrates x , but it also raises the question of y .
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You may already have made a few recommendations for future research in your discussion section, but the conclusion is a good place to elaborate and look ahead, considering the implications of your findings in both theoretical and practical terms.
- Based on these conclusions, practitioners should consider …
- To better understand the implications of these results, future studies could address …
- Further research is needed to determine the causes of/effects of/relationship between …
When making recommendations for further research, be sure not to undermine your own work. Relatedly, while future studies might confirm, build on, or enrich your conclusions, they shouldn’t be required for your argument to feel complete. Your work should stand alone on its own merits.
Just as you should avoid too much self-criticism, you should also avoid exaggerating the applicability of your research. If you’re making recommendations for policy, business, or other practical implementations, it’s generally best to frame them as “shoulds” rather than “musts.” All in all, the purpose of academic research is to inform, explain, and explore—not to demand.
Make sure your reader is left with a strong impression of what your research has contributed to the state of your field.
Some strategies to achieve this include:
- Returning to your problem statement to explain how your research helps solve the problem
- Referring back to the literature review and showing how you have addressed a gap in knowledge
- Discussing how your findings confirm or challenge an existing theory or assumption
Again, avoid simply repeating what you’ve already covered in the discussion in your conclusion. Instead, pick out the most important points and sum them up succinctly, situating your project in a broader context.
The end is near! Once you’ve finished writing your conclusion, it’s time to wrap up your thesis or dissertation with a few final steps:
- It’s a good idea to write your abstract next, while the research is still fresh in your mind.
- Next, make sure your reference list is complete and correctly formatted. To speed up the process, you can use our free APA citation generator .
- Once you’ve added any appendices , you can create a table of contents and title page .
- Finally, read through the whole document again to make sure your thesis is clearly written and free from language errors. You can proofread it yourself , ask a friend, or consider Scribbr’s proofreading and editing service .
Here is an example of how you can write your conclusion section. Notice how it includes everything mentioned above:
The current research aimed to identify acoustic speech characteristics which mark the beginning of an exacerbation in COPD patients.
The central questions for this research were as follows: 1. Which acoustic measures extracted from read speech differ between COPD speakers in stable condition and healthy speakers? 2. In what ways does the speech of COPD patients during an exacerbation differ from speech of COPD patients during stable periods?
All recordings were aligned using a script. Subsequently, they were manually annotated to indicate respiratory actions such as inhaling and exhaling. The recordings of 9 stable COPD patients reading aloud were then compared with the recordings of 5 healthy control subjects reading aloud. The results showed a significant effect of condition on the number of in- and exhalations per syllable, the number of non-linguistic in- and exhalations per syllable, and the ratio of voiced and silence intervals. The number of in- and exhalations per syllable and the number of non-linguistic in- and exhalations per syllable were higher for COPD patients than for healthy controls, which confirmed both hypotheses.
However, the higher ratio of voiced and silence intervals for COPD patients compared to healthy controls was not in line with the hypotheses. This unpredicted result might have been caused by the different reading materials or recording procedures for both groups, or by a difference in reading skills. Moreover, there was a trend regarding the effect of condition on the number of syllables per breath group. The number of syllables per breath group was higher for healthy controls than for COPD patients, which was in line with the hypothesis. There was no effect of condition on pitch, intensity, center of gravity, pitch variability, speaking rate, or articulation rate.
This research has shown that the speech of COPD patients in exacerbation differs from the speech of COPD patients in stable condition. This might have potential for the detection of exacerbations. However, sustained vowels rarely occur in spontaneous speech. Therefore, the last two outcome measures might have greater potential for the detection of beginning exacerbations, but further research on the different outcome measures and their potential for the detection of exacerbations is needed due to the limitations of the current study.
I have clearly and concisely answered the main research question .
I have summarized my overall argument or key takeaways.
I have mentioned any important limitations of the research.
I have given relevant recommendations .
I have clearly explained what my research has contributed to my field.
I have not introduced any new data or arguments.
You've written a great conclusion! Use the other checklists to further improve your dissertation.
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In a thesis or dissertation, the discussion is an in-depth exploration of the results, going into detail about the meaning of your findings and citing relevant sources to put them in context.
The conclusion is more shorter and more general: it concisely answers your main research question and makes recommendations based on your overall findings.
While it may be tempting to present new arguments or evidence in your thesis or disseration conclusion , especially if you have a particularly striking argument you’d like to finish your analysis with, you shouldn’t. Theses and dissertations follow a more formal structure than this.
All your findings and arguments should be presented in the body of the text (more specifically in the discussion section and results section .) The conclusion is meant to summarize and reflect on the evidence and arguments you have already presented, not introduce new ones.
For a stronger dissertation conclusion , avoid including:
- Important evidence or analysis that wasn’t mentioned in the discussion section and results section
- Generic concluding phrases (e.g. “In conclusion …”)
- Weak statements that undermine your argument (e.g., “There are good points on both sides of this issue.”)
Your conclusion should leave the reader with a strong, decisive impression of your work.
The conclusion of your thesis or dissertation shouldn’t take up more than 5–7% of your overall word count.
The conclusion of your thesis or dissertation should include the following:
- A restatement of your research question
- A summary of your key arguments and/or results
- A short discussion of the implications of your research
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National Research Council (US) and Institute of Medicine (US) Panel to Review the National Children's Study Research Plan. The National Children's Study Research Plan: A Review. Washington (DC): National Academies Press (US); 2008.
The National Children's Study Research Plan: A Review.
- Hardcopy Version at National Academies Press
6 Conclusions and Recommendations
D uring the past several months the panel has met and reviewed the research plan for the National Children’s Study (NCS), various working papers of the study, and additional documents provided by the National Institute of Child Health and Human Development. The panel believes that this landmark study offers an unparalleled opportunity to examine the effects of environmental influences on child health and development, as well as to explore the complex interactions between genes and environments. The database derived from the study will be valuable for investigating the hypotheses described in the research plan as well as additional hypotheses that will evolve.
The critique, suggestions, and recommendations offered in the preceding chapters, therefore, are intended to improve the capabilities of the study to carry out the important mandate of the Children’s Health Act of 2000. This chapter highlights the panel’s key conclusions and recommendations resulting from its review organized by chapter and subject area.
CHAPTER 2: NCS GOALS, CONCEPTUAL FRAMEWORK, AND CORE HYPOTHESES
Conclusion 2-1: The stated overall and specific goals for the NCS—and the design of the NCS to achieve those goals—largely reflect the stipulations of the Children’s Health Act of 2000. In the broadest terms, the NCS goals and design are responsive to the call in the act for a “national longitudinal study of environmental influences (including physical, chemical, biological, and psychosocial) on children’s health and development.” Conclusion 2-2: The large, nationally representative, equal probability sample design, together with the inclusion of a large number of outcome and exposure measures over a long time span, are major strengths of the NCS. In particular, the sample design is an appropriate platform for the study, considering resource constraints, the need to represent all population groups and geographic areas, and the difficulty of devising an alternative disproportionate sampling scheme that would not unduly disadvantage some groups and areas that turn out to be of analytical interest. Conclusion 2-3: In four overarching areas, the NCS design, as represented in the research plan, is not, or may not be, optimal for achieving the goals of the Children’s Health Act. These areas are: insufficient attention to understanding disparities in child health and development among population groups of children defined by race, ethnicity, language, socioeconomic status, and geographic area, which the act explicitly mandates; inadequate conceptualization of important constructs, including health and development, and an overemphasis on disease and impairment relative to health and functionality and on risk factors relative to protective health-promoting factors; impaired data collection schedules and types of measures to support evaluation of some of the effects of chronic and intermittent exposures on child health and development; and underappreciation of the challenges to obtaining the highest possible quality of data from an observational design, which include the decentralized data collection structure of the study and limitations on the frequency of home and clinic visits and on the collection of medical and other administrative records for study participants.
Recommendation 2-1: The NCS should give priority attention to seeking ways to bolster the ability of the study to contribute to understanding of health disparities among children in different racial, ethnic, and other population groups, including the reestablishment of a working group to oversee this area and the encouragement of appropriate adjunct studies. Recommendation 2-2: The NCS should seek resources and develop methods to obtain more frequent in-person measures and medical and other administrative records data on study participants.
Recommendation 2-3: The NCS should clearly define the key constructs of child health and development and more fully develop a conceptual framework for understanding child health and development over the course of infancy, childhood, and adolescence.
Using the Vanguard Centers as Pilots
Recommendation 2-4: We strongly urge the NCS to delay enrollment at new sites to make effective use of initial findings from participant enrollment and data collection in the Vanguard Center sites to improve study procedures, as appropriate, and to refine key concepts, hypotheses, and measures of outcomes and exposures. Throughout the life of the study, the NCS should use the Vanguard Centers to pilot test and experiment with data collection methods and instrumentation.
CHAPTER 3: PRIORITY OUTCOME AND EXPOSURE MEASURES
Recommendation 3-1: The NCS should consider replacing research on subclinical maternal hypothyroidism as a factor in adverse pregnancy outcomes with research on the effects of a broader set of maternal physical and mental health conditions, such as maternal depression, maternal perceived stress, and maternal periodontal disease. Recommendation 3-2: The NCS should develop refined, detailed protocols for investigating all pregnancy outcomes, specifically a detailed protocol for obtaining information on various types of pregnancy loss, before beginning data collection at the Vanguard Centers, given that pregnancy outcomes are among the first outcomes to be examined; many outcomes lack clarity in measurement; and there are important questions regarding the adequacy of statistical power and the planned data collection (for example, the need for prepregnancy measurements of some exposures).
Neurodevelopment and Behavior and Child Health and Development
Recommendation 3-3: The NCS should develop a clearer rationale for the selection of specific neurodevelopment and behavior disorders to be considered in the study and a clearer conceptual basis for the assessment of normal child health and development trajectories and outcomes. Clarity is needed to guide the choice of outcome measures and exposure measures and the frequency and types of contacts (at the home, in clinics) with study participants in order to obtain the best information possible within resource and burden constraints.
Recommendation 3-4: The NCS should develop a clearer rationale for its hypotheses about factors that may increase the incidence of asthma. These should focus on prenatal and early life risk factors.
Obesity and Growth
Recommendation 3-5: The NCS should reevaluate its main hypotheses to be addressed in the study of childhood obesity and consider adopting a broader approach that incorporates social and psychological factors as well as biogenetic ones. Such an approach would help the study identify the constellations of key factors and their interrelationships that are important to understand in order to develop the most effective public health measures to reduce childhood obesity.
Recommendation 3-6: The NCS should consider replacing research on repeated mild traumatic brain injury (rMTBI) with more nuanced research on other injury-related topics, such as environmental factors in childhood injuries and the effects of clinical response to injury (treatment or nontreatment).
Hormonally Active Agents and Reproductive Development
Recommendation 3-7: The NCS should develop refined and detailed protocols for studying reproductive development outcomes, which, as presented in the research plan, often lack clarity in measurement and research design. Outcomes that are measured at birth for which there is little time to refine research protocols require immediate attention. The NCS should use results from the Vanguard Centers, such as estimates of the prevalence of specific reproductive development outcomes, to assist in protocol development, and it should consider the usefulness of substudies of high-exposure population groups.
Demographic and Socioeconomic Measures
Recommendation 3-8: The NCS should add to its well-planned battery of demographic and socioeconomic measures questions on immigrant generation, languages spoken, and, if possible, the legal status of the parents and child.
Chemical Exposure Measures
Recommendation 3-9: The NCS should consider the use of personal air sampling methods for a subsample of participating women and their children for measuring exposure to air pollutants. Recommendation 3-10: The NCS should incorporate methodology to measure paternal exposure to environmental chemicals (both persistent and nonpersistent). More generally, the NCS should consider collecting for fathers, not only chemical exposures, but also biological samples and interview data on paternal characteristics that may affect children’s health and development to the same degree as it collects such information for mothers.
Physical Exposure Measures
Recommendation 3-11: The NCS should provide a clearer rationale for some of the housing and neighborhood conditions it proposes to measure and revisit its data collection plans to ensure that needed measures are obtained at developmental stages when children may be more vulnerable to risk factors. The goal should be a set of measures and data collection plans that are optimal with regard to analytic utility and response burden.
Psychosocial Exposure Measures
Recommendation 3-12: The NCS should reconsider its psychosocial measures to ensure that they will provide high-quality data for outcomes of interest for child health and development. In the face of resource and respondent burden constraints, the NCS should emphasize the quality and analytic utility of information, even if some measures must be dropped in order to substitute other assessments more desirable on various grounds. Recommendation 3-13: The NCS should dedicate a portion of funds to support research and development of reliable and valid instruments of key psychosocial measures that are practical and economical to administer.
Biological Exposure Measures
Recommendation 3-14: The NCS should review some of the proposed measures of biological exposures, such as maternal glucose metabolism and child cortisol levels, to ensure that the proposed times for data collection are appropriate for capturing the underlying exposure.
Recommendation 3-15: The NCS should adopt a clear mechanism by which genetic association studies are internally and, optimally, externally validated before any results are published or released to the media. The NCS should also revise its proposed “established” candidate gene approach to take advantage of the new information emanating from the current wave of genome-wide association studies, with appropriate replication. Recommendation 3-16: The NCS should consider consolidating its genetics studies in order to reduce costs and to coordinate the best science at the least cost to the project. One approach would be to simply collect the biological samples and properly store them for later genetic analysis when a better selection of polymorphisms and cost-effective genotyping across studies are possible.
Recommendation 3-17: The NCS should add measures of access to and quality of services, including medical care, education, child care, and services, as potential mediators of health and development outcomes and to improve the assessment of information obtained through maternal reports.
Recommendation 3-18: To facilitate linkages of NCS data with environmental exposures from other databases, such as measures of demographics, crime, government programs, and pollution, the NCS should develop a plan for geocoding the residential addresses from prebirth through adulthood of all participating children to standard census geographic units. In addition, the study should develop arrangements by which researchers, both inside and outside the NCS study centers, can access geocodes for respondent addresses and are encouraged to perform linkages and make their environmental information available to the NCS analysis community. Such arrangements must safeguard the confidentiality of NCS respondents.
CHAPTER 4: STUDY DESIGN, DATA COLLECTION, AND ANALYSIS
Conclusion 4-1: We strongly endorse the use of probability sampling to select the NCS national sample of births. Conclusion 4-2: While we endorse the decision to select an equal probability national sample of births as a reasonable strategy given the many key scientific objectives of the NCS, we recognize that a proportionate representation of the study’s target population will result in estimates for some subgroups that are not as precise as they would be had those groups been oversampled. Conclusion 4-3: The process of identifying births from a national sample of households is complex and subject to numerous sources of attrition of uncertain magnitude. Because of this, it will be difficult to predict how many households must be initially selected to produce a probability sample of 1,000 births in each of the NCS sites. Recommendation 4-1: The NCS should consider modifying the sampling design to allow for flexibility in increasing the number of study participants in the event that the estimated number of screened households needed to reach 1,000 births per primary sampling unit (PSU) is incorrect. Recommendation 4-2: The NCS should consider the proposed household enumeration approach to be experimental and should conduct carefully designed field studies to clearly establish the statistical and practical implications of the proposed adjudicated listing approach. Recommendation 4-3: To ensure a diverse exposure profile in the sample, the NCS should consider a careful assessment of variation in ambient exposure to chemical agents within each PSU. If the set of segments in a PSU can be classified by combined exposure to a group of important chemical agents, this information could then be used to form varying exposure-level strata for segment sampling in each PSU and thus ensure a range of ambient exposure to relevant environmental agents.
Conclusion 4-4: The data collection model adopted by the NCS is complex, will challenge the abilities of the staff and coordinating center to achieve a uniform and consistent national data collection, and may compromise key study objectives. Conclusion 4-5: The NCS research plan does not provide sufficient information on the use of data collection guidelines and quality-control procedures to enable evaluation of the planned implementation of a uniform national data collection system. Conclusion 4-6: The NCS research plan does not address directly the issue of respondent burden, except to say that “some” effort is being made to reduce it, nor does the plan make clear the total number of hours the respondent must commit to the study. In particular, in light of the estimate of the interview length (4 hours) for the baseline interview, a critical collection for the study, the research plan pays little attention to respondent burden and its impact on the quality of the data. Conclusion 4-7: The NCS research plan provides little information concerning best methods for sample recruitment to achieve initial and follow-up target response rates, sample maintenance and sample retention procedures for implementation at the study sites, community involvement plans consistent with the uniform implementation of data collection procedures, or contingency plans to support study sites that do not achieve target response rates. Conclusion 4-8: The NCS research plan does not address the ongoing methodological needs of the study—to study data collection procedures and instruments, conduct experiments, and evaluate the quality of the survey operations and the quality of the data—nor does the plan make the best use of the Vanguard Centers. Recommendation 4-4: The NCS should consider ways in which the survey data collection could be consolidated into a smaller number of highly qualified survey organizations. Recommendation 4-5: Because of the complexity of the proposed organizational model for data collection and the difficulty of maintaining the quality and uniformity of data collection procedures across a large number of study sites, the NCS program office should establish and monitor strict standards for enrollment, retention, and data collection at each of the study sites and be prepared to take immediate corrective action if sites do not meet high-quality standards in data collection. Recommendation 4-6: The NCS should prepare a plan for monitoring progress of the study in reaching its sample size goals. As part of the plan, the NCS should take advantage of the experience of the Vanguard Centers to evaluate initial enrollment rates, the effectiveness and potential respondent burden of the interview instrument, and the ability of the Vanguard Centers to obtain the required household environmental measures reliably. Recommendation 4-7: To resolve issues that arise during data collection, the NCS should set aside sufficient resources to maintain an ongoing program of methods research and field experimentation. Among the issues that might be addressed in this research are the reliability and validity of previously untested survey questions and measurement strategies, the effectiveness of sample retention procedures, predictors of response outcomes associated with sample initial recruitment and subsequent annual retention, error implications of unit nonresponse, adjustment strategies for unit nonresponse, and methods for dealing with item nonresponse.
Data Analysis and Dissemination
Recommendation 4-8: The NCS should begin planning for the rapid dissemination of the core study data, subject to respondent protection, to the general research community and for supporting the use of the data after dissemination. The costs of implementing this plan should be estimated and set aside in future NCS budgets. Dissemination includes not only the publication of findings through reports and scientific papers and the production of documented data files for researchers, but also active support in the use of NCS data by the broadest possible range of qualified investigators.
CHAPTER 5: ETHICAL PROCEDURES AND COMMUNITY ENGAGEMENT
Criteria for giving information to participants.
Recommendation 5-1: The NCS should define the criteria and the process for deciding what individual clinical and research information, such as environmental assessments, test results, and survey scales, will be given to children and their families.
Protection and Release of Information
Recommendation 5-2: NCS and non-NCS investigators should be given equal access to the full NCS data as soon as they are cleaned and documented. To protect respondent confidentiality, all analyses should be performed with the kind of strict safeguards employed by the Census Bureau research data centers.
Recommendation 5-3: The NCS should engage communities in selected study implementation, data analysis, and data interpretation activities that go beyond recruitment. The NCS should consider requiring every study center to formulate a more detailed plan to engage and collaborate with local communities.
In summary, it is clear from our review that the NCS offers not only enormous potential, but also a large number of conceptual, methodological, and administrative challenges. In addition, funding uncertainties make it difficult to plan beyond the relatively short period for which funds have been appropriated. Like the scientists associated with the study itself, we are eager for it to succeed. We present our conclusions and recommendations in the hope that, as it goes forward, the NCS will achieve its intended objectives and serve as a model of methodological and substantive contributions to important scientific and policy discussions on children’s health and development.
- Cite this Page National Research Council (US) and Institute of Medicine (US) Panel to Review the National Children's Study Research Plan. The National Children's Study Research Plan: A Review. Washington (DC): National Academies Press (US); 2008. 6, Conclusions and Recommendations.
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- ETHICAL PROCEDURES AND COMMUNITY ENGAGEMENT
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The conclusion is intended to help the reader understand why your research should matter to them after they have finished reading the paper. A conclusion is not merely a summary of the main topics covered or a re-statement of your research problem, but a synthesis of key points and, if applicable, where you recommend new areas for future research. For most college-level research papers, one or two well-developed paragraphs is sufficient for a conclusion, although in some cases, more paragraphs may be required in summarizing key findings and their significance.
Conclusions. The Writing Center. University of North Carolina; Conclusions. The Writing Lab and The OWL. Purdue University.
Importance of a Good Conclusion
A well-written conclusion provides you with important opportunities to demonstrate to the reader your understanding of the research problem. These include:
- Presenting the last word on the issues you raised in your paper . Just as the introduction gives a first impression to your reader, the conclusion offers a chance to leave a lasting impression. Do this, for example, by highlighting key findings in your analysis that advance new understanding about the research problem, that are unusual or unexpected, or that have important implications applied to practice.
- Summarizing your thoughts and conveying the larger significance of your study . The conclusion is an opportunity to succinctly re-emphasize the "So What?" question by placing the study within the context of how your research advances past research about the topic.
- Identifying how a gap in the literature has been addressed . The conclusion can be where you describe how a previously identified gap in the literature [described in your literature review section] has been filled by your research.
- Demonstrating the importance of your ideas . Don't be shy. The conclusion offers you the opportunity to elaborate on the impact and significance of your findings. This is particularly important if your study approached examining the research problem from an unusual or innovative perspective.
- Introducing possible new or expanded ways of thinking about the research problem . This does not refer to introducing new information [which should be avoided], but to offer new insight and creative approaches for framing or contextualizing the research problem based on the results of your study.
Bunton, David. “The Structure of PhD Conclusion Chapters.” Journal of English for Academic Purposes 4 (July 2005): 207–224; Conclusions. The Writing Center. University of North Carolina; Kretchmer, Paul. Twelve Steps to Writing an Effective Conclusion. San Francisco Edit, 2003-2008; Conclusions. The Writing Lab and The OWL. Purdue University; Assan, Joseph. "Writing the Conclusion Chapter: The Good, the Bad and the Missing." Liverpool: Development Studies Association (2009): 1-8.
Structure and Writing Style
I. General Rules
The function of your paper's conclusion is to restate the main argument . It reminds the reader of the strengths of your main argument(s) and reiterates the most important evidence supporting those argument(s). Do this by stating clearly the context, background, and necessity of pursuing the research problem you investigated in relation to an issue, controversy, or a gap found in the literature. Make sure, however, that your conclusion is not simply a repetitive summary of the findings. This reduces the impact of the argument(s) you have developed in your essay.
When writing the conclusion to your paper, follow these general rules:
- Present your conclusions in clear, simple language. Re-state the purpose of your study, then describe how your findings differ or support those of other studies and why [i.e., what were the unique or new contributions your study made to the overall research about your topic?].
- Do not simply reiterate your findings or the discussion of your results. Provide a synthesis of arguments presented in the paper to show how these converge to address the research problem and the overall objectives of your study.
- Indicate opportunities for future research if you haven't already done so in the discussion section of your paper. Highlighting the need for further research provides the reader with evidence that you have an in-depth awareness of the research problem and that further investigations should take place.
Consider the following points to help ensure your conclusion is presented well:
- If the argument or purpose of your paper is complex, you may need to summarize the argument for your reader.
- If, prior to your conclusion, you have not yet explained the significance of your findings or if you are proceeding inductively, use the end of your paper to describe your main points and explain their significance.
- Move from a detailed to a general level of consideration that returns the topic to the context provided by the introduction or within a new context that emerges from the data.
The conclusion also provides a place for you to persuasively and succinctly restate the research problem, given that the reader has now been presented with all the information about the topic . Depending on the discipline you are writing in, the concluding paragraph may contain your reflections on the evidence presented. However, the nature of being introspective about the research you have conducted will depend on the topic and whether your professor wants you to express your observations in this way.
NOTE : If asked to think introspectively about the topics, do not delve into idle speculation. Being introspective means looking within yourself as an author to try and understand an issue more deeply, not to guess at possible outcomes or make up scenarios not supported by the evidence.
II. Developing a Compelling Conclusion
Although an effective conclusion needs to be clear and succinct, it does not need to be written passively or lack a compelling narrative. Strategies to help you move beyond merely summarizing the key points of your research paper may include any of the following strategies:
- If your essay deals with a critical, contemporary problem, warn readers of the possible consequences of not attending to the problem proactively.
- Recommend a specific course or courses of action that, if adopted, could address a specific problem in practice or in the development of new knowledge.
- Cite a relevant quotation or expert opinion already noted in your paper in order to lend authority and support to the conclusion(s) you have reached [a good place to look is research from your literature review].
- Explain the consequences of your research in a way that elicits action or demonstrates urgency in seeking change.
- Restate a key statistic, fact, or visual image to emphasize the most important finding of your paper.
- If your discipline encourages personal reflection, illustrate your concluding point by drawing from your own life experiences.
- Return to an anecdote, an example, or a quotation that you presented in your introduction, but add further insight derived from the findings of your study; use your interpretation of results to recast it in new or important ways.
- Provide a "take-home" message in the form of a succinct, declarative statement that you want the reader to remember about your study.
III. Problems to Avoid
Failure to be concise Your conclusion section should be concise and to the point. Conclusions that are too lengthy often have unnecessary information in them. The conclusion is not the place for details about your methodology or results. Although you should give a summary of what was learned from your research, this summary should be relatively brief, since the emphasis in the conclusion is on the implications, evaluations, insights, and other forms of analysis that you make. Strategies for writing concisely can be found here .
Failure to comment on larger, more significant issues In the introduction, your task was to move from the general [the field of study] to the specific [the research problem]. However, in the conclusion, your task is to move from a specific discussion [your research problem] back to a general discussion [i.e., how your research contributes new understanding or fills an important gap in the literature]. In short, the conclusion is where you should place your research within a larger context [visualize your paper as an hourglass--start with a broad introduction and review of the literature, move to the specific analysis and discussion, conclude with a broad summary of the study's implications and significance].
Failure to reveal problems and negative results Negative aspects of the research process should never be ignored. These are problems, deficiencies, or challenges encountered during your study should be summarized as a way of qualifying your overall conclusions. If you encountered negative or unintended results [i.e., findings that are validated outside the research context in which they were generated], you must report them in the results section and discuss their implications in the discussion section of your paper. In the conclusion, use your summary of the negative results as an opportunity to explain their possible significance and/or how they may form the basis for future research.
Failure to provide a clear summary of what was learned In order to be able to discuss how your research fits within your field of study [and possibly the world at large], you need to summarize briefly and succinctly how it contributes to new knowledge or a new understanding about the research problem. This element of your conclusion may be only a few sentences long.
Failure to match the objectives of your research Often research objectives in the social sciences change while the research is being carried out. This is not a problem unless you forget to go back and refine the original objectives in your introduction. As these changes emerge they must be documented so that they accurately reflect what you were trying to accomplish in your research [not what you thought you might accomplish when you began].
Resist the urge to apologize If you've immersed yourself in studying the research problem, you presumably should know a good deal about it [perhaps even more than your professor!]. Nevertheless, by the time you have finished writing, you may be having some doubts about what you have produced. Repress those doubts! Don't undermine your authority by saying something like, "This is just one approach to examining this problem; there may be other, much better approaches that...." The overall tone of your conclusion should convey confidence to the reader.
Assan, Joseph. "Writing the Conclusion Chapter: The Good, the Bad and the Missing." Liverpool: Development Studies Association (2009): 1-8; Concluding Paragraphs. College Writing Center at Meramec. St. Louis Community College; Conclusions. The Writing Center. University of North Carolina; Conclusions. The Writing Lab and The OWL. Purdue University; Freedman, Leora and Jerry Plotnick. Introductions and Conclusions. The Lab Report. University College Writing Centre. University of Toronto; Leibensperger, Summer. Draft Your Conclusion. Academic Center, the University of Houston-Victoria, 2003; Make Your Last Words Count. The Writer’s Handbook. Writing Center. University of Wisconsin Madison; Miquel, Fuster-Marquez and Carmen Gregori-Signes. “Chapter Six: ‘Last but Not Least:’ Writing the Conclusion of Your Paper.” In Writing an Applied Linguistics Thesis or Dissertation: A Guide to Presenting Empirical Research . John Bitchener, editor. (Basingstoke,UK: Palgrave Macmillan, 2010), pp. 93-105; Tips for Writing a Good Conclusion. Writing@CSU. Colorado State University; Kretchmer, Paul. Twelve Steps to Writing an Effective Conclusion. San Francisco Edit, 2003-2008; Writing Conclusions. Writing Tutorial Services, Center for Innovative Teaching and Learning. Indiana University; Writing: Considering Structure and Organization. Institute for Writing Rhetoric. Dartmouth College.
Don't Belabor the Obvious!
Avoid phrases like "in conclusion...," "in summary...," or "in closing...." These phrases can be useful, even welcome, in oral presentations. But readers can see by the tell-tale section heading and number of pages remaining to read, when an essay is about to end. You'll irritate your readers if you belabor the obvious.
Assan, Joseph. "Writing the Conclusion Chapter: The Good, the Bad and the Missing." Liverpool: Development Studies Association (2009): 1-8.
Another Writing Tip
New Insight, Not New Information!
Don't surprise the reader with new information in your conclusion that was never referenced anywhere else in the paper and, as such, the conclusion rarely has citations to sources. If you have new information to present, add it to the discussion or other appropriate section of the paper. Note that, although no actual new information is introduced, the conclusion, along with the discussion section, is where you offer your most "original" contributions in the paper; the conclusion is where you describe the value of your research, demonstrate that you understand the material that you’ve presented, and locate your findings within the larger context of scholarship on the topic, including describing how your research contributes new insights or valuable insight to that scholarship.
Assan, Joseph. "Writing the Conclusion Chapter: The Good, the Bad and the Missing." Liverpool: Development Studies Association (2009): 1-8; Conclusions. The Writing Center. University of North Carolina.
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Plasma Processing of Materials: Scientific Opportunities and Technological Challenges (1991)
Chapter: 1 summary, findings, conclusions, and recommendations, 1 summary, findings, conclusions, and recommendations.
This study focuses on the plasma processing of materials, a technology that impacts and is of vital importance to several of the largest manufacturing industries in the world. Foremost among these industries is the electronics industry, in which plasma-based processes are indispensable for the manufacture of very large-scale integrated (VLSI) microelectronic circuits (or chips). Plasma processing of materials is also a critical technology in the aerospace, automotive, steel, biomedical, and toxic waste management industries. Because plasma processing is an integral part of the infrastructure of so many American industries, it is important for both the economy and the national security that America maintain a strong leadership role in this technology.
A plasma is a partially or fully ionized gas containing electrons, ions, and neutral atoms or molecules. In Chapter 2 , the panel categorizes different kinds of plasmas and focuses on properties of man-made low-energy, highly collisional plasmas that are particularly useful in materials processing applications. The outstanding properties of most plasmas applied to processing of materials are associated with nonequilibrium conditions. These properties present a challenge to the plasma scientist and an opportunity to the technologist. The opportunities for materials processing stem from the ability of a plasma to provide a highly excited medium that has no chemical or physical counterpart in a natural, equilibrium environment. Plasmas alter the normal pathways through which chemical systems evolve from one stable state to another, thus providing the potential to produce materials with properties that are not attainable by any other means.
Applications of plasma-based systems used to process materials are diverse because of the broad range of plasma conditions, geometries, and excitation methods that may be used. The scientific underpinnings of plasma applications are multidisciplinary and include elements of electrodynamics, atomic science, surface science, computer science, and industrial process control. Because of the diversity of applications and the multidisciplinary nature of the science, scientific understanding lags technology. This report highlights this critical issue.
A summary of the many industrial applications of plasma-based systems for processing materials is included in Chapter 2 . Electronics and aerospace are the two major industries that are served by plasma processing technologies, although the automotive industry is likely to become a significant user of plasma-processed materials like those now in widespread use in the aerospace industry. The critical role of plasma processing technology in industry is illustrated in Chapter 2 .
For the electronics industry more than for any other considered by the panel, the impact of—and the critical and urgent need for—plasma-based materials processing is overwhelming. Thus Chapter 3 further elucidates plasma processing of electronic materials and, in particular, the use of plasmas in fabricating microelectronic components. The plasma equipment industry is an integral part of the electronics industry and has experienced dramatic growth in recent years because of the increasing use of plasma processes to meet the demands of fabricating devices with continually shrinking dimensions. In this country, the plasma equipment industry
is composed of many small companies loosely connected to integrated circuit manufacturers. In Japan, on the other hand, equipment vendors and device manufacturers are tightly linked and are often parts of the same company.
Plasma processes used today in fabricating microelectronic devices have been developed largely by time-consuming, costly, empirical exploration. The chemical and physical complexity of plasma-surface interactions has so far eluded the accurate numerical simulation that would enable process design. Similarly, plasma reactors have also been developed by trial and error. This is due, in part, to the fact that reactor design is intimately intertwined with the materials process for which it will be used. Nonetheless, fundamental studies of surface processes and plasma phenomena—both experimental and numerical—have contributed to process development by providing key insights that enable limitation of the broad process-variable operating space. The state of the science that underpins plasma processing technology in the United States is outlined in Chapter 4 . Although an impressive arsenal of both experimental and numerical tools has been developed, significant gaps in understanding and lack of instrumentation limit progress.
The broad interdisciplinary nature of plasma processing is highlighted in the discussion of education issues outlined in Chapter 5 , which addresses the challenges and opportunities associated with providing a science education in the area of plasma processing. For example, graduate programs specifically focused on plasma processing are rare because of insufficient funding of university research programs in this field. By contrast, both Japan and France have national initiatives that support education and research in plasma processing.
FINDINGS, CONCLUSIONS, AND RECOMMENDATIONS
Finding and Conclusion : In recent years, the number of applications requiring plasmas in the processing of materials has increased dramatically. Plasma processing is now indispensable to the fabrication of electronic components and is widely used in the aerospace industry and other industries. However, the United States is seeing a serious decline in plasma reactor development that is critical to plasma processing steps in the manufacture of VLSI microelectronic circuits. In the interest of the U.S. economy and national defense, renewed support for low-energy plasma science is imperative.
Finding and Conclusion : The demand for technology development is outstripping scientific understanding of many low-energy plasma processes. The central scientific problem underlying plasma processing concerns the interaction of low-energy collisional plasmas with solid surfaces. Understanding this problem requires knowledge and expertise drawn from plasma physics, atomic physics, condensed matter physics, chemistry, chemical engineering, electrical engineering, materials science, computer science, and computer engineering. In the absence of a coordinated approach, the diversity of the applications and of the science tends to diffuse the focus of both.
Finding : Technically, U.S. laboratories have made many excellent contributions to plasma processing research—making fundamental discoveries, developing numerical algorithms, and inventing new diagnostic techniques. However, poor coordination and inefficient transfer of insights gained from this research have inhibited its use in the design of new plasma reactors and processes.
Finding : The Panel on Plasma Processing of Materials finds that plasma processing of materials is a critical technology that is necessary to implement key recommendations contained in the National Research Council report Materials Science and Engineering for the 1990s (National Academy Press, Washington, D.C., 1989) and to enhance the health of technologies as identified in Report of the National Critical Technologies Panel (U.S. Government Printing Office, Washington, D.C., 1991). Specifically, plasma processing is an essential element in the synthesis and processing arsenal for manufacturing electronic, photonic, ceramic, composite, high-performance metal, and alloy materials.
Accordingly, the panel recommends:
Plasma processing should be identified as a component program of the Federal Initiative on advanced materials synthesis and processing that currently is being developed by the Office of Science and Technology Policy.
Through such a Plasma Processing Program, federal funds should be allocated specifically to stimulate focused research in plasma processing, both basic and applied, consistent with the long-term economic and defense goals of the nation.
The Plasma Processing Program should not only provide focus on common goals and promote coordination of the research performed by the national laboratories, universities, and industrial laboratories, but also integrate plasma equipment suppliers into the program.
Finding and Conclusion : Currently, computer-based modeling and plasma simulation are inadequate for developing plasma reactors. As a result, the detailed descriptions required to guide the transfer of processes from one reactor to another or to scale processes from a small to a large reactor are not available. Until we understand how geometry, electromagnetic design, and plasma-surface interactions affect material properties, the choice of plasma reactor for a given process will not be obvious, and costly trial-and-error methods will continue to be used. Yet there is no fundamental obstacle to improved modeling and simulation nor to the eventual creation of computer-aided design (CAD) tools for designing plasma reactors. The key missing ingredients are the following:
A reliable and extensive plasma data base against which the accuracy of simulations of plasmas can be compared . Plasma measurement technologies are sophisticated, but at present experiments are performed on a large variety of different reactors under widely varying conditions. A coordinated effort to diagnose simple, reference reactors is necessary to generate the necessary data base for evaluation of simulation results and to test new and old experimental methodology.
A reliable and extensive input data base for calculating plasma generation, transport, and surface interaction . The dearth of basic data needed for simulation of plasma generation, transport, and surface reaction processes results directly from insufficient generation of data, insufficient data compilation, insufficient distribution of data, and insufficient funding of these activities. The critical basic data needed for simulations and experiments have not been prioritized. For plasma-surface interactions, in particular, lack of data has precluded the formation of mechanistic models on which simulation tools are based. Further experimental studies are needed to elucidate these mechanisms.
Efficient numerical algorithms and supercomputers for simulating magnetized plasmas in three dimensions . The advent of unprecedented supercomputer capability in the next 5 to 10 years will have a major impact in this area, provided that current simulation methods are expanded to account for multidimensional effects in magnetized plasmas.
The Plasma Processing Program should include a thrust toward development of computer-aided design tools for developing and designing new plasma reactors.
The Plasma Processing Program should emphasize a coordinated approach toward generating the diagnostic and basic data needed for improved plasma and plasma-surface simulation capability.
A program to extend current algorithms for plasma reactor simulation should be included among the activities funded under the umbrella of the federal High
Performance Computing and Communications program 1 developed by the Office of Science and Technology Policy and started in FY92.
Finding and Conclusion : In the coming decade, custom-designed and custom-manufactured chips, i.e ., application-specific integrated circuits (ASICs), will gain an increasing fraction of the world market in microelectronic components. This market, in turn, will belong to the flexible manufacturer who uses a common set of processes and equipment to fabricate many different circuit designs. Such flexibility in processing will result only from real understanding of processes and reactors. On the other hand, plasma processes in use today have been developed using a combination of intuition, empiricism, and statistical optimization. Although it is unlikely that detailed, quantitative, first-principles-based simulation tools will be available for process design in the near future, design aids such as expert systems, which can be used to guide engineers in selecting initial conditions from which the final process is derived, could be developed if gaps in our fundamental understanding of plasma chemistry were filled.
Finding and Conclusion : Three areas are recognized by the panel as needing concerted, coordinated experimental and theoretical research: surface processes, plasma generation and transport, and plasma-surface interactions. For surface processes, studies using well-controlled reactive beams impinging on well-characterized surfaces are essential for enhancing our understanding and developing mechanistic models. For plasma generation and transport, chemical kinetic data and diagnostic data are needed to augment the basic plasma reactor CAD tool. For studying plasma-surface interactions, there is an urgent need for in situ analytical tools that provide information on surface composition, electronic structure, and material properties.
Finding and Conclusion : Breakthroughs in understanding the science will be paced by development of tools for the characterization of the systems. To meet the coming demands for flexible device manufacturing, plasma processes will have to be actively and precisely controlled. But today no diagnostic techniques exist that can be used unambiguously to determine material properties related to device yield. Moreover, the parametric models needed to relate diagnostic data to process variables are also lacking.
According, the panel recommends:
The Plasma Processing Program should be dedicated in part to the development of plasma process expert systems.
A coordinated program should be supported to generate basic data and simulation of surface processes, plasma generation and transport, and plasma-surface interactions.
A program should be supported that focuses on development of new instrumentation for real-time, in situ monitoring for control and analysis.
Finding : Research resources in low-energy plasma science in the United States are eroding at an alarming rate. U.S. scientists trained in this area in the 1950s and early 1960s are retiring or are moving to other areas of science for which support is more forthcoming. When compared to those in Japan and France, the U.S. educational infrastructure in plasma processing lacks focus, coordination, and funding. As a result, the United States will not be prepared to maintain its leading market position in plasma processing, let alone capture more market share as the plasma process industry grows into the 21st century.
Finding : Graduate programs are not offering adequate educational opportunities in the science of weakly ionized, highly collisional plasmas. An informal survey by the panel indicated that only a few U.S. universities offer formal course work in this science and that there are
insufficient texts on collisional plasmas and plasma processing. These deficiencies are a direct result of low-level funding for graduate research in plasma processing and low-energy plasmas.
Finding and Conclusion : The most serious need in undergraduate education is adequate, modern teaching laboratories. Due to the largely empirical nature of many aspects of plasma processing, proper training in the traditional scientific method, as provided in laboratory classes, is a necessary component of undergraduate education. The Instrumentation and Laboratory Improvement Program sponsored by the National Science Foundation has been partly successful in fulfilling these needs, but it is not sufficient.
Finding and Conclusion : Research experiences for undergraduates made available through industrial cooperative programs or internships are essential for high-quality technical education. But teachers and professors themselves must first be educated in low-energy plasma science and plasma processing before they can be expected to educate students. Industrial-university links can also help to impart a much needed, longer-term view to industrial research efforts.
As part of the Plasma Processing Program, government and industry together should support cooperative programs specific to plasma processing with universities and national laboratories.
A program should be established to provide industrial internships for teachers and professors in the area of plasma processing.
Plasma processing of materials is a critical technology to several of the largest manufacturing industries in the world—electronics, aerospace, automotive, steel, biomedical, and toxic waste management. This book describes the relationship between plasma processes and the many industrial applications, examines in detail plasma processing in the electronics industry, highlights the scientific foundation underlying this technology, and discusses education issues in this multidisciplinary field.
The committee recommends a coordinated, focused, and well-funded research program in this area that involves the university, federal laboratory, and industrial sectors of the community. It also points out that because plasma processing is an integral part of the infrastructure of so many American industries, it is important for both the economy and the national security that America maintain a strong leadership role in this technology.
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