Plastic substrates offer many advantages over traditional rigid substrates such as low mass, toughness, and flexibility. Flexible electronics could have a wide range of applications including foldable electronics , sensors, displays, medical devices , solar cells , deployable spacecraft structures , and even smart clothing . Fabrication of these devices is a challenge due to the limited temperature tolerance of flexible polymers. The most common approach focuses on modified, low temperature versions of conventional deposition processes, which result in amorphous and/or polycrystalline Si on polymeric substrates . Due to the limited process-temperature tolerance of the polymers, the carrier mobility of the deposited layers is very low and often unacceptable for high-speed electronics. Pulsed laser approaches , where laser annealing of the surface region partially crystallizes the deposited layers, have achieved some success but their work with plastic substrates remains a topic of study and their mobility remain low (less than or on the order of 1 cm2/V-s) . Organic semiconductors provide naturally integrated and low-cost solutions, but even very high quality single crystals of these materials have mobility in the range of 1-2 cm2/V-s and 10-20 cm2/V-s for n-type and p-type devices, respectively . Our strategy is entirely different. We intend to use the ion-cut process to transfer single crystal semiconductor layers (group IV and III-V semiconductors) onto polymeric flexible substrates. The single crystalline nature of the thin semiconductor layers will facilitate higher carrier mobility and other pertinent parameters for high-speed flexible electronics
We request support for two undergraduate students to participate each year in a Research Experience for Undergraduates (REU) project. All of the REU activities will be fully integrated into our recently NSF-funded project (DMR-0992277). Our objective is to introduce well-qualified undergraduate students who are interested in electronic materials related subjects to a graduate research environment. We will expose undergraduate students to ongoing research opportunities and outreach activities in our laboratories. The ultimate goal is to enhance the students REU experience and to improve the likelihood of their retention in scientific research. Successful outcomes of this endeavor will be the enhanced motivation of undergraduates to become graduate students involved in meaningful research and outreach activities. A final report will be submitted at the end of their employment. A total of six students will be supported by this supplement over the projects three year duration. We are in a good position to achieve the objectives of this supplemental proposal.
|Effective start/end date||7/1/09 → 6/30/13|
- National Science Foundation (NSF): $711,999.00