A Simple Fabrication Process of T-Shaped Gates Using a Deep-UV/Electron-Beam/Deep-UV Tri-Layer Resist System and Electron-Beam Lithography

Abstract

A new fabrication process of T-shaped gates has been developed using a deep-UV/electron-beam/deep-UV (DUV/EB/DUV) tri-layer resist system and electron-beam lithography for the first time. The simple process accomplished a submicron T-shaped gate by a single exposure and a single development step. The narrow/wide/narrow opening of the DUV/EB/DUV resist structure can be accurately controlled by the e-beam dosage and the development conditions. Differences in the sensitivities of the DUV resist and the EB resist were investigated. Due to the lower sensitivity of the adopted DUV resist to the electron beam, the smaller opening of the DUV resist layer was obtained. The higher sensitivity of the EB resist resulted in a wider opening in the middle resist layer. A 0.15-µm-gate-length T-shaped gate can be easily formed by the short-process-time and low-production-cost hybrid DUV/EB/DUV resist approach.

Scalable Fabrication of Edge Contacts to 2D Materials: Implications for Quantum Resistance Metrology and 2D Electronics

“…Inspired by the method of forming edge contacts to graphene/hBN heterostructures, here we report a microfabrication strategy for the scalable microfabrication of electrical contacts to 2D materials based on the tri-layer resist system, which does not require encapsulation of the 2D material by hBN. Recently, we have used this method to produce nearly 3000 contacts to graphene and demonstrated the largest, most accurate array of graphene quantum resistors, using epitaxial graphene on silicon carbide (epigraphene) .…”