| This thesis presents key process methodologies for plastic-substrate electronics and creative innovation on both the futuristic three-dimensional (3-D) conformable devices and electronic clothing.; Using silicone gel mountant, several inorganic and organic thin-film electronics were fabricated on low-cost, lightweight, flexible plastic substrates, including hydrogenated amorphous silicon (a-Si:H) photovoltaic cells, a-Si:H thin-film transistor (TFT) array backplanes for gamma ray detectors, and pentacence organic TFTs (OTFTs). Devices demonstrated on plastic films show excellent performance comparable with those fabricated on conventional rigid, fragile substrates such as glass and semiconductor wafers.; In the device-on-plastic (DOP) development, a broad range of plastic films was investigated. Polyimide films, including transparent LaRC-CP1 ® and semitransparent Kapton® were examined to build thin-film photovoltaic cells, detector arrays, and organic and inorganic transistors. Low-cost, transparent polymeric films including PET and PEN were investigated and exploited for low-temperature electronic development including organic light-emitting diodes (OLEDs) and organic thin-film transistors-driven liquid crystal displays.; In the gamma ray detector work, 100μm Vacrel® and 40μm Riston® dry-film photopolymers were used, respectively, to fabricate deep wells and form novel 3-D tenting structures that cover and seal the wells and define the liftoff patterns for electrodes used in the gamma ray detector. The MEMS-like detector process was then further combined with thin-film technology and plastic-substrate electronic processing to fabricate a-Si:H TFT array backplanes on flexible Kapton® polyimide substrates with the well detectors integrated on the TFT backplanes.; Innovative device processes were developed for the fabrication of futuristic electronics, including 3-D conformable devices and electronic clothing. In this development, a 15μm photosensitive dry-film material was used to conformably pattern OTFTs on a variety of non-planar 3-D surfaces and fabrics. The small-molecule pentacene organic semiconductor was used as the active material in the OTFTs and gate-regulated device electrical characteristics were observed and demonstrated on several rigid 3-D objects such as a key ring, bolt washer, and door hinge, and fabrics, including 250 thread-count sheets and Kevlar® high temperature cloth.; The above demonstrations, including plastic-substrate electronics, 3-D conformable devices, and electronic clothing illustrate what thin-film technology is capable of achieving and point toward an era of electronics on anything and anywhere. |
