SEMICONDUCTOR DEVICE

摘要

A semiconductor device includes a substrate which includes a first face. The device also includes a buffer layer, a semiconductor layer, source and drain electrodes, and a gate electrode. A trench is formed on the semiconductor layer so that the trench surrounds the source electrode, the drain electrode, and the gate electrode in a plan view, the trench passes through the semiconductor layer and the buffer layer, and a bottom of the trench reaches at least an inside of the substrate. A distance from the first face of the substrate to the bottom of the trench is 100 nm or more in a thickness direction of the substrate.

主权项

1. A semiconductor device comprising:
a substrate which includes a first face and a second face facing the first face and in which at least the first face comprises silicon; a buffer layer which comprises a first group III nitride semiconductor and includes a third face and a fourth face facing the third face and in which the third face faces the first face of the substrate; a semiconductor layer which comprises a second group III nitride semiconductor and includes a fifth face and a sixth face facing the fifth face and in which the fifth face faces the first face of the substrate via the buffer layer; a source electrode formed over the sixth face of the semiconductor layer; a drain electrode formed over the sixth face of the semiconductor layer; a gate electrode formed over the sixth face of the semiconductor layer and which is formed between the source electrode and the drain electrode in a plan view; wherein a trench is formed on the sixth face of the semiconductor layer so that the trench surrounds the source electrode, the drain electrode, and the gate electrode in a plan view, the trench passes through the semiconductor layer and the buffer layer, and a bottom of the trench reaches at least an inside of the substrate, and the semiconductor device further comprises: a metal film which is formed in the trench and which is formed at least from the substrate to the buffer layer in a height direction of the trench, the metal film and the gate electrode comprising the same layer; and a gate insulating film formed on the sixth face of the semiconductor layer, the gate electrode being formed on an upper surface of the gate insulating film, and an upper surface of the metal film being substantially coplanar with the upper surface of the gate insulating film, wherein a distance from the first face of the substrate to the bottom of the trench is 100 nm or more in a thickness direction of the substrate.