University of Houston, United States
Keywords: RF, sensor, detector, compound semiconductor, gallium, flexible electronicsSilicon-based Field Effect Transistors (FETs), which currently control the market share in RF applications, are limited in speed, exhibit low-power and low break-down voltages. Compound semiconductor FETs with high-mobility/speed, high breakdown voltage, low-leakage, higher power and > 100 GHz operation are perfect candidates to meet the performance demands. However, they are very expensive compared to silicon-based devices because of the high cost of wafers used. Furthermore, they are brittle, which prevents them from deployment in conformal and flexible electronics. We have developed a unique technology of high-performance, flexible compound semiconductor devices that can enable next-generation RF systems that are flexible, conformal, inexpensive while delivering performance beyond the scope of silicon-based devices. Our unique technology is based on single-crystal-like compound semiconductor thin films with high mobility on flexible substrates by roll-to-roll manufacturing. Thin-film Transistors (TFTs) have been made with these films with current levels 100-1000 times and mobility levels 100 times that of flexible TFTs. We have also demonstrated flexible and light-weight GaAs photodetector arrays on metal substrates with high responsivity, ultra-fast response times, high current output and long-term stability. We have recently extended our technology to epitaxial gallium oxide films on flexible substrates which opens up even higher power applications.