GAN-BASED MIS-HEMT DEVICE HAVING Г-SHAPED GATE AND PREPARATION METHOD

作者：WANG, Hong; CHEN, Jingxiong; LIU, Xiaoyi

来源：2019-12-31, OTHER, CN2019130993.

A GaN-based MIS-HEMT device having a Г-shaped gate and preparation method therefor. The device comprises a structure such as an AlGaN/GaN heterojunction epitaxial layer (1). The device further comprises a Г-shaped gate electrode (6). The Г-shaped gate electrode (6) comprises a gate cap and a gate foot. One end of the gate foot is connected to a part of the lower surface of the gate cap, and the other end thereof is connected to an upper surface of a gate dielectric layer (4) partially exposed at a second opening. The remaining lower surface of the gate cap is connected to an upper surface of a passivation layer (5). By combining G-line or I-line photolithography, comprising contact photolithography and stepping photolithography, with a metal lift-off process or metal lithography process, a part of the gate (6) is made to contact the gate dielectric layer (4), and the other part thereof is made to contact the passivation layer (5) by means of alignment at an opening of the passivation layer (5), such that the linewidth of the gate (6) is greatly reduced under the extreme linewidth of photolithography. A field plate is introduced to the Г-shaped gate structure (6). The field plate modulates the electric field strength distribution of a conductive trench on the side of the gate (6) close to a drain (3), thereby improving a breakdown voltage of a device.

• 出版日期2019-12-31
• 单位华南理工大学