Optical lithography technique for formation of gate structures with nanometre geometries

A novel process, using standard thin film and optical lithography techniques, has been demonstrated which is capable of yielding linewidths considerably below 0.25 mu m. Furthermore, inherent in this selfaligned process is the formation of high aspect-ratio T- or gamma-shaped profiles for FET-like devices requiring reduced gate resistance. This new technique was recently used to fabricate nominal, 0.25 mu m gate length pseudomorphic high electron mobility transistors (PM-HEMTs).