Workshop :: Flexible Hybrid Electronics
 

A panel of experts discussed current directions in Flexible Hybrid Electronics in a public workshop after completing their study to examine the worldwide status and trends in this field, sponsored by the United States National Science Foundation (NSF) and the Office of Naval Research (ONR). This FREE workshop was held on June 30, 2009 at NSF, 4201 Wilson Boulevard, Stafford II, Room 595, Arlington, VA 22230.

 

Workshop Proceedings

 

Introduction to the Study   This study considers an international assessment of research and development in flexible hybrid electronics and systems. Flexible hybrid electronics incorporate both organic and inorganic semiconductors on a flexible backplane to realize the advantages of both types of semiconductor materials.   Background There is an emerging demand for electronic circuits and systems on flexible substrates. This trend is in keeping with the spread of electronic functionality everywhere and the emergence of new materials, systems, device architectures, and fabrication processes to create new types of electronic circuits. At the heart of this trend is the functional integration of many types of materials - inorganic, organic, and even biological materials. Such integration permits new functionality and enhanced performance. This field has quickly become a rapidly growing research area, and one where the U.S. and EU are vying for the lead (Fig. 1).

Sponsors

 

Fig. 1. Rapid growth of scientific papers in hybrid, flexible electronics and related subjects. The EU produces about as many papers as the US, but Asian countries are behind--Japan with 13 papers in 2007 has the most. The on-line version of the Science Citation Index was the database, with the filter: TS = ("HYBRID ELECTRONIC*") OR ("ORGANIC ELECTRONIC*") OR ("FLEXIBLE ELECTRONIC*") OR ("PRINTABLE ELECTRONIC*").

 

This has led to projections that this new sector - flexible hybrid electronics - will be an important part of the economy during the next 20 years, with significant growth beginning in a few years. This has led many countries and organizations to start investing heavily in basic research that creates enabling technologies in areas important to the growth of flexible electronics and also in basic science issues that contribute to such systems. Since this new field is diverse, involving many technologies, materials, devices, etc., a plan to systematically advance learning would be helpful. Some basic research is already being done in relevant areas, but more needs to be done to accelerate progress. More importantly, a structured effort to assess international progress could help ensure the competitiveness of the United States in this important new area.

 

Some successful examples of past research that has had an impact in this area include the development of flexible backplanes based on organic semiconductor transistors for electronic paper [1,2]. Such transistors are inherently more easily printable and their performance levels are adequate for several applications. As requirements for components in flexible/printable circuits and systems get more stringent, new material systems including inorganic semiconductors, organic single crystals, nanotubes, and advanced wiring must be investigated in conjunction with suitable processing techniques. Equally important is the integration of multiple functionality in systems by combining various components such as sensors, actuators, and interface electronics such as antennae. The first examples of such systems are emerging [3,4]

 

Purpose

The purpose of this study is to inform program managers and researchers of the international state of the art in flexible hybrid electronics, to identify leading researchers and institutions abroad for possible collaboration, to identify promising topics for future research, and to provide information to program managers for decisions about future research directions. The proposed study will use WTEC's methodology based on an expert panel conducting site visits to overseas laboratories where the best work in flexible printable semiconductors is done. This effort will be combined with literature reviews, coupled with the panel's own research and analysis. The findings of this study will result in deliverables consisting of briefings to sponsors, public workshops, and a final report. Collectively they should provide a comprehensive, peer-reviewed set of evaluations of overseas R&D on flexible organic semiconductors, with comparisons to that conducted in the United States. There are a number of expected benefits from such a study. One important benefit will come from the process itself. Interested programs across NSF and from other agencies will be working together to better define the field and its needs together. Using the findings of this study and other inputs they can collectively work out a roadmap for future research. There will be other tangible benefits. For example, the study is a good vehicle to address some of the key issues of critical importance to programs officers and the research community, including:

 

• What is the position of foreign R&D relative to the United States?
• What are the barriers and gaps of research that can be learned overseas?
• What are the major innovations and emerging ideas that are worth exploring in the U. S.?
• What are the opportunities for international collaboration to tackle bigger technical challenges by combining complementary resources and strengths?

Scope

 

The scope of the present study will be determined through discussions between sponsoring agencies and the expert panelists to determine which questions most need answers. It will include a detailed examination of flexible, printed electronics research efforts underway in Europe, and possibly, Asia. Attention will be paid to the semiconductor systems, additional components, and fabrication methods. The functional integration of biological, organic, and inorganic materials into hybrid devices and systems is an important technological necessity. However, this is a major interdisciplinary challenge that requires a focused and organized effort on a sufficient scale. At the heart is the goal of understanding how dissimilar materials and unique properties: (a) Organize on top of each other, (b) Interact with each other chemically and electronically, (c) How information can be exchanged from one type of material to another within the context of a device, (d) How processing methods influence the layers, and (e) How scale, including nanoscale and mesoscale effects impact the points listed above. The importance of fabrication (and hence manufacturing) methods must also be emphasized. Key to the implementation of the types of systems we are contemplating, is the ability to fabricate them using roll-to-roll methods which provide economies of throughput and scale. For example, a company Heliovolt [5] has revolutionized inorganic thin-film solar cell fabrication based on the CuInGaSe materials system by developing very innovative roll-to-roll processes and print-plate based technologies [5], which significantly alters the costs of fabricating solar cells. The development and implementation of such processing methods are crucial to the economy of the United States.

 

References

1. A. Dodabalapur, Transistors for flexible electronics. Materials Today, Vol. 8, No. 4, pp 2-8. (2006).
2. J. A. Rogers, et al, Proceedings of the National Academy of Sciences, Vol. 98, 4835. (2002)
3. V. Subramanian, Towards printed low-cost RFID tags. Presented at the Second Advanced Technology Workshop on Printing Intelligent Organic and Molecular Electronics Technologies, Boston 2003.
4. T. Someya, et al., IEEE Trans. Electron Devices, Vol. 52. No. 11. (2005).
5. Heliovolts FASST technology, www.heliovolt.com

Chair's Meeting

• Draft Statement of Work
• Dodabalapur Presentation on 9/3/8
• Shelton Presentation on 9/3/8
• Draft Minutes of the Chair's Meeting of 9/3/8

 

Kickoff Meeting

• Agenda
• WTEC Methods for International R&D Assessments
• Milestones for WTEC International Studies
• Dodabalapur Presentation on 12/3/08
• Draft Minutes of 12/3/08
•   

Final Report

• Final Report - July 2011