SEMICONDUCTOR DEVICE AND METHOD OF MANUFACTURING THE SAME
A semiconductor device includes a first semiconductor layer formed over a substrate; a second semiconductor layer formed over the first semiconductor layer; electrodes formed over the second semiconductor layer; and a third semiconductor layer formed on the second semiconductor layer; wherein the third semiconductor layer is formed so as to surround each element, in which the electrodes are formed, and wherein the third semiconductor layer is a semiconductor layer of a conductivity type whose polarity is opposite to that of carriers produced in the first semiconductor layer.
1 . A semiconductor device comprising:
a first semiconductor layer formed over a substrate;
a second semiconductor layer formed over the first semiconductor layer;
electrodes formed over the second semiconductor layer; and
a third semiconductor layer formed on the second semiconductor layer;
wherein the third semiconductor layer is formed so as to surround each element, in which the electrodes are formed, and
wherein the third semiconductor layer is a semiconductor layer of a conductivity type whose polarity is opposite to that of carriers produced in the first semiconductor layer.
2 . The semiconductor device according to claim 1 ,
wherein the first semiconductor layer, the second semiconductor layer, and the third semiconductor layer are nitride semiconductors.
3 . The semiconductor device according to claim 1 ,
wherein electrons are produced in the first semiconductor layer near an interface between the first semiconductor layer and the second semiconductor layer, and
wherein the third semiconductor layer is p-type.
4 . The semiconductor device according to claim 1 ,
wherein the electrodes are a gate electrode, a source electrode, and a drain electrode, and are formed over the second semiconductor layer in a region surrounded by the third semiconductor layer.
5 . The semiconductor device according to claim 4 ,
wherein the semiconductor device is a high electron mobility transistor.
6 . The semiconductor device according to claim 1 ,
wherein the electrodes are a cathode electrode and an anode electrode, and are formed over the second semiconductor layer in a region surrounded by the third semiconductor layer.
7 . The semiconductor device according to claim 1 ,
wherein the first semiconductor layer is composed of a material including GaN.
8 . The semiconductor device according to claim 1 ,
wherein the second semiconductor layer is composed of a material including AlGaN.
9 . The semiconductor device according to claim 1 ,
wherein the second semiconductor layer is n-type.
10 . The semiconductor device according to claim 1 ,
wherein the third semiconductor layer is composed of a material including GaN.
11 . The semiconductor device according to claim 1 ,
wherein an electrode is formed on the third semiconductor layer.
12 . A method of manufacturing a semiconductor device, the method comprising:
sequentially layering films over a substrate, the films including formation materials for a first semiconductor layer, a second semiconductor layer, and a third semiconductor layer;
forming the third semiconductor layer by removing a portion of the film including the formation material for the third semiconductor layer; and
forming electrodes over the second semiconductor layer;
wherein the third semiconductor layer is formed so as to surround each element, in which the electrodes are formed, and
wherein the third semiconductor layer is a semiconductor layer of a conductivity type whose polarity is opposite to that of carriers produced in the first semiconductor layer.
13 . The method of manufacturing a semiconductor device according to claim 12 ,
wherein, in the forming of electrodes, an electrode is additionally formed on the third semiconductor layer.
14 . The method of manufacturing a semiconductor device according to claim 12 ,
wherein, in the forming of electrodes, a gate electrode, a source electrode, and a drain electrode are formed.
15 . The method of manufacturing a semiconductor device according to claim 12 ,
wherein, in the forming of electrodes, a cathode electrode and an anode electrode are formed.
16 . A method of manufacturing a semiconductor device, the method comprising:
sequentially forming and layering a first semiconductor layer and a second semiconductor layer over a substrate;
forming a mask on the second semiconductor layer, the mask including an opening at a predetermined region;
forming a third semiconductor layer on a portion of the second semiconductor layer, the portion being exposed by the opening of the mask;
removing the mask; and
forming electrodes over the second semiconductor layer;
wherein the third semiconductor layer is formed so as to surround each element, in which the electrodes are formed, and
wherein the third semiconductor layer is a semiconductor layer of a conductivity type whose polarity is opposite to that of carriers produced in the first semiconductor layer.
17 . The method of manufacturing a semiconductor device according to claim 16 ,
wherein the mask is amorphous, and
wherein the third semiconductor layer is formed by metal-organic vapor phase epitaxy or molecular beam epitaxy.
18 . The method of manufacturing a semiconductor device according to claim 16 ,
wherein, in the forming of electrodes, an electrode is additionally formed on the third semiconductor layer.
19 . The method of manufacturing a semiconductor device according to claim 16 ,
wherein, in the forming of electrodes, a gate electrode, a source electrode, and a drain electrode are formed.
20 . The method of manufacturing a semiconductor device according to claim 16 ,
wherein, in the forming of electrodes, a cathode electrode and an anode electrode are formed.