Thin Film Transistors (TFT) are a unique type of field effect transistor. Generally used as components of flat panel displays and projections, TFTs are applied to semiconductor materials to improve image stability and quality. Sarnoff’s history in TFT technologies dates back over forty years — from pioneering work on integrated display drivers for LCDs in the 1970s to the new design methods of today that allow circuits to tolerate inherent shortcomings. Entire industries continue to develop around display technology, utilizing materials and technologies developed here at Sarnoff.
Sarnoff has a number of capabilities for creating and developing the next generation of thin film transistors. Higher performance needs led to the development of CMOS polysilicon TFTs for integrated display driver circuits. Using our CMOS-on-plastic technology has allowed Sarnoff to demonstrate the highest performing transistors and the fastest circuits ever fabricated directly on plastic. Our work in organic TFTs enables video-capable TFT LCDs and has led to the capabilities for analog and digital circuits on plastic substrates, including frequency dividers, voltage comparators and ring oscillators. Sarnoff’s most recent development has been with graphene TFTs, which utilize a two-dimensional form of carbon that promises much higher performance than conventional silicon. Sarnoff is able to integrate graphene TFTs onto silicon CMOS chips, allowing the conventional IC to exploit superior performance for even the most demanding signal processing functions.
Thin film transistors developed at Sarnoff are incorporated into many of today’s technologies — from commonplace applications such as flat panel displays to use in active matrix displays that provide a much brighter and sharper image. TFTs can be found in imaging and sensing arrays such as phased array antennas, structural health monitoring arrays and rugged digital x-ray panels. Electronic systems other than pixel arrays have advantages when fabricated on flexible substrates. For example, very low cost RFID tags can be manufactured using TFT technology and used for item level tracking.
