Fabrication of 50nm T-Gate on GaN Substrate

Abstract

This paper reports New advances in e-beam lithography which have made possible the fabrication of high electron mobility transistors (HEMT) on GaN substrate with gate length well in the nanometer regime. Using PMMA/PMMA-MMA Pseudo-bilayer resists technology with electron beam lithography preparation 50nm gate length T-gate. A method of in a single lithographic step and a development step, which can be applied to simplify the process and get a more narrow gate. The ratio of head to footprint of the T gate is controllable. The way meets the need of the device fabrication.