▎ 摘　　要

NOVELTY - Semiconductor device comprises an epitaxial structure formed on a substrate (101), where the epitaxial structure has an indium-aluminum nitride (InAlN)/gallium nitride (GaN) heterojunction, and further comprises at least two-dimensional material layer (102) distributed between the source electrode (109) and the drain electrode (107). The two-dimensional material layer has a gate dielectric part and passivation part located on both sides of the gate dielectric part. The gate of the device is in indirect contact with the epitaxial structure through the gate dielectric part. The passivation part is located between the gate and source of the device, and between the gate and drain of the device. The material of the two-dimensional material layer is a carbon-based two-dimensional material, optionally carbon nanotubes, graphene or graphitic carbon nitride. USE - Used as semiconductor device. ADVANTAGE - The device: utilizes two-dimensional material as a gate dielectric and a passivation structure, so as to reduce leakage current of the device; and has improved breakdown voltage. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for a method for preparing the semiconductor device. DESCRIPTION OF DRAWING(S) - The drawing shows a schematic diagram of the third structure of the semiconductor device. Substrate (101) Two-dimensional material layer (102) Buffer layer (103) Gan layer (104) Insertion layer (105) Inaln layer (106) Drain electrode (107) Gate (108) Source electrode (109) Inaln power device (300) First test electrode (301) Second test electrode (302) Third test electrode (303)