COMPOUND SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME
An embodiment of a compound semiconductor device includes: a substrate; an electron channel layer and an electron supply layer formed over the substrate; a gate electrode, a source electrode and a drain electrode formed on or above the electron supply layer; a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and a hole barrier layer formed between the electron supply layer and the p-type semiconductor layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.
1 . A compound semiconductor device comprising:
a substrate;
an electron channel layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed on or above the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole barrier layer formed between the electron supply layer and the p-type semiconductor layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.
2 . The compound semiconductor device according to claim 1 , wherein
composition of the electron supply layer is represented by Al x Ga 1-x N (0<x<1), and
composition of the hole barrier layer is represented by Al y Ga 1-y N (x<y≦1).
3 . The compound semiconductor device according to claim 1 , wherein
composition of the electron supply layer is represented by Al x Ga 1-x N (0<x<1), and
composition of the hole barrier layer is represented by In z Ai 1-z N (0≦z≦1).
4 . The compound semiconductor device according to claim 1 , wherein the electron channel layer is a GaN layer.
5 . The compound semiconductor device according to claim 1 , wherein the p-type semiconductor layer is a GaN layer which contains Mg.
6 . The compound semiconductor device according to claim 1 , further comprising a gate insulating film formed between the gate electrode and the p-type semiconductor layer.
7 . The compound semiconductor device according to claim 1 , further comprising a termination film which covers the electron supply layer in each of a region between the gate electrode and the source electrode and a region between the gate electrode and the drain electrode.
8 . A power supply apparatus comprising
a compound semiconductor device, which comprises:
a substrate;
an electron channel layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed on or above the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole barrier layer formed between the electron supply layer and the p-type semiconductor layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.
9 . An amplifier comprising
a compound semiconductor device, which comprises:
a substrate;
an electron channel layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed on or above the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole barrier layer formed between the electron supply layer and the p-type semiconductor layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.
10 . A method of manufacturing a compound semiconductor device, comprising:
forming an electron channel layer and an electron supply layer over the substrate;
forming a gate electrode, a source electrode and a drain electrode on or above the electron supply layer;
forming a p-type semiconductor layer which is located between the electron supply layer and the gate electrode, before the forming the gate electrode; and
forming a hole barrier layer which is located between the electron supply layer and the p-type semiconductor layer, before the forming the p-type semiconductor layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.
11 . The method of manufacturing a compound semiconductor device according to claim 10 , wherein
composition of the electron supply layer is represented by Al x Ga 1-x N (0<x<1), and
composition of the hole barrier supply layer is represented by Al y Ga 1-y N (x<y≦1).
12 . The method of manufacturing a compound semiconductor device according to claim 10 , wherein
composition of the electron supply layer is represented by Al x Ga 1-x N (0<x<1), and
composition of the hole barrier supply layer is represented by In z Ai 1-z N (0≦z≦1).
13 . The method of manufacturing a compound semiconductor, device according to claim 10 , wherein the forming the hole barrier supply layer comprises eliminating Ga from a surface of the electron supply layer.
14 . The method of manufacturing a compound semiconductor device according to claim 10 , wherein the forming the p-type semiconductor layer comprises performing patterning by dry etching with the hole barrier layer as an etching stopper.
15 . The method of manufacturing a compound semiconductor device according to claim 10 , wherein the electron channel layer is a GaN layer.
16 . The method of manufacturing a compound semiconductor device according to claim 10 , wherein the p-type semiconductor layer is a GaN layer which contains Mg.
17 . The method of manufacturing a compound semiconductor device according to claim 10 , further comprising forming a gate insulating film between the gate electrode and the p-type semiconductor layer.
18 . The method of manufacturing a compound semiconductor device according to claim 10 , further comprising forming a termination film which covers the electron supply layer in each of a region between the gate electrode and the source electrode and a region between the gate electrode and the drain electrode.