COMPOUND SEMICONDUCTOR AND METHOD OF MANUFACTURING THE SAME
An embodiment of a compound semiconductor device includes: a substrate; an electron transport layer and an electron supply layer formed over the substrate; a gate electrode, a source electrode and a drain electrode formed over the electron supply layer; a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and a hole canceling layer formed between the electron supply layer and the p-type semiconductor layer, the hole canceling layer containing a donor or a recombination center and canceling a hole.
1 . A compound semiconductor device, comprising:
a substrate;
an electron transport layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed over the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole canceling layer formed between the electron supply layer and the p-type semiconductor layer, the hole canceling layer containing a donor or a recombination center and canceling a hole.
2 . The compound semiconductor device according to claim 1 , wherein the p-type semiconductor layer is a GaN layer which contains Mg.
3 . The compound semiconductor device according to claim 1 , wherein the hole canceling layer contains a p-type impurity.
4 . The compound semiconductor device according to claim 3 , wherein the hole canceling layer contains Mg as the p-type impurity.
5 . The compound semiconductor device according to claim 1 , wherein the hole canceling layer contains Si as the donor.
6 . The compound semiconductor device according to claim 1 , wherein the hole canceling layer contains at least one selected from the group Fe, Cr, Co, Ni, Ti, V, and Sc as the recombination center.
7 . The compound semiconductor device according to claim 1 , further comprising 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.
8 . The compound semiconductor device according to claim 7 , 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).
9 . The compound semiconductor device according to claim 7 , 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).
10 . 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.
11 . The compound semiconductor device according to claim 1 , further comprising a termination film that 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.
12 . A power supply apparatus, comprising
a compound semiconductor device, which comprises:
a substrate;
an electron transport layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed over the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole canceling layer formed between the electron supply layer and the p-type semiconductor layer, the hole canceling layer containing a donor or a recombination center, and canceling a hole.
13 . An amplifier, comprising
a compound semiconductor device, which comprises:
a substrate;
an electron transport layer and an electron supply layer formed over the substrate;
a gate electrode, a source electrode and a drain electrode formed over the electron supply layer;
a p-type semiconductor layer formed between the electron supply layer and the gate electrode; and
a hole canceling layer formed between the electron supply layer and the p-type semiconductor layer, the hole canceling layer containing a donor or a recombination center, and canceling a hole.
14 . A method of manufacturing a compound semiconductor device, comprising:
forming an electron transport layer and an electron supply layer over a substrate;
forming a gate electrode, a source electrode and a drain electrode over 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 canceling layer which is located between the electron supply layer and the p-type semiconductor layer, before the forming the p-type semiconductor layer, the hole canceling layer containing a donor or a recombination center and canceling a hole.
15 . The method of manufacturing a compound semiconductor device according to claim 14 , wherein the p-type semiconductor layer is a GaN layer which contains Mg.
16 . The method of manufacturing a compound semiconductor device according to claim 14 , wherein the hole canceling layer contains a p-type impurity.
17 . The method of manufacturing a compound semiconductor device according to claim 16 , wherein the hole canceling layer contains Mg as the p-type impurity.
18 . The method of manufacturing a compound semiconductor device according to claim 14 , wherein the hole canceling layer contains Si as the donor.
19 . The method of manufacturing a compound semiconductor device according to claim 14 , wherein the hole canceling layer contains at least one selected from the group Fe, Cr, Co, Ni, Ti, V, and Sc as the recombination center.
20 . The method of manufacturing a compound semiconductor device according to claim 14 , further comprising forming a hole barrier layer which is located between the electron supply layer and the hole canceling layer, before the forming the hole canceling layer, a band gap of the hole barrier layer being larger than that of the electron supply layer.