Flexible electronics is an exciting technology which requires expertise in several areas such as physics, chemistry and engineering. Therefore, the students in our group will not only gain experience with state-of-the-art instrumentation and techniques but also gain an understanding of the inter-disciplinary nature of this area. Students also interact with our collaborators at several US universities and laboratories, as well as with collaborators abroad. Flexible electronics has many new applications, ranging from large area sensors to flexible displays to roll-up photovoltaics. However, to make flexible electronics a viable technology a number of key components still need to be developed including memory, logic, analog devices and amplifiers. The Flexible Electronics group in the Materials Science Department at UTD, is focused in the development and integration of these different components. Current projects include:
Sensors for Detecting Radiation. We work in new technologies for nuclear threat detection, including the fundamental interactions of neutrons and charged particles with matter. We design and fabricate complex circuits and test devices for sensitivity and radiation hardness. We work in collaboration with the Gen-II fabrication facility at the Flexible Display Center at Arizona State University.
Nano-Engineered Materials for Flexible Electronics. (Metals, Dielectrics, Semiconductors). The students work on the development of nano-structured materials for contacts, dielectrics and semiconductors for flexible electronics. They learn about fundamental materials synthesis and characterization as well as device fabrication to correlate materials properties with device performance.
Process Integration (nMOS, pMOS, CMOS, etc). In this area the group explores the issues associated with the effect of materials properties and chemistry and structure of the electrode/organic interface with the electrical performance of organic thin film transistor (OTFT) devices. This work will be performed in collaboration with Centro de Investigacion en Materials Avanzados (CIMAV), which is one of Mexico's leading research laboratories in nanoscale science.
Device modeling and Simulation. We work in electrostatic simulations to model electronic transport in molecular systems, which in conjunction with device fabrication and testing, aid in improving the understanding of organic semiconductor materials and devices. We fabricate representative organic semiconductor devices with different molecules, grain sizes, grain orientations, and other parameters; measure their electrical characteristics, and develop, validate, and refine original mathematical and computer models to describe the electrical characteristics of the devices.
Energy Harvesting and Storage. In this area the group works on the development of alternate energy storage and harvesting technologies. In particular, the group focuses on thermoelectric interface engineering, novel acceptor and donor materials for organic solar cells, and novel MEMS devices based on piezoelectric active materials. Super capacitors based on high-k particles blended in organic materials are also studied for energy storage applications.
- D. Mao, M.A. Quevedo-Lopez, H. N. Alshareef, H. Stiegler and B. E. Gnade, “Optimization of Poly(vinylidene fluoride-trifluoroethylene) Films as Non-volatile Memory for Flexible Electronics” Organic Electronics 11(5) 925-932 (2010)
- S Gowrisanker, M.A. Quevedo-Lopez, H. N. Alshareef, B. Gnade. S. Venugopal, R. Krishna, K. Kaftanoglu, D. Allee, “A Novel Low Temperature Integration of Hybrid CMOS Devices on Flexible Substrates Organic Electronics”, Organic Electronics 10 1217-1222 (2009)
- D. Mao, I. Mejia, H. Stiegler, B. E. Gnade, and M. A. Quevedo-Lopez, “Polarization behavior of poly-vinylidene fluoride-trifluoroethylene copolymer ferroelectric thin film capacitors for nonvolatile memory application in flexible electronics” Journal of Applied Physics, 108 094102 (2010)
- M. A. Quevedo-Lopez, J. J. Chambers, M. R. Visokay, A. Shanware, and L. Colombo “Thermal stability of hafnium-silicate and plasma-nitrided hafnium silicate films studied by Fourier transfor,m infrared spectroscopy” Applied Physics Letters 87 012902 (2005).
- M. A. Quevedo-Lopez, M. El-Bouanani, S. Addepalli, J. L.Duggan, B. E. Gnade R. M. Wallace M.R.Visokay, M. Douglas, M.J. Bevan, and L. Colombo, “Hafnium inter-diffusion studies from hafnium silicate into Silicon” Applied Physics Letters 79 4192 (2001).