Development of a Robust and Highly Precise Process for Sub-100 nm T-gates

Abstract:
This work presents a fabrication process for T-gates in high-frequency electronic devices, such as high electron mobility transistors, using a 100 kV electron beam lithography system. By optimizing the proximity effect correction through precise determination of the short-range blur, mechanically stable T-gates can be defined in a single-exposure, even under conditions of high current, thick resist, and large-area writing, while maintaining sub-100 nm feature sizes. Furthermore, the T-gates produced via this approach demonstrate excellent mechanical stability, achieving a wing-to-foot ratio as high as 20.