Voltage-sustaining layer for semiconductors
View Patent ↗conductivity type, a first region doped with the first conductivity type, a second region doped with the second conductivity type, N first oxide layers and K second oxide layers. The second region is located above the second drain region. The first region is located above the drain region and at a side of the second region. The source region is located above the first region and the second region. The first oxide layers are located at a side in the second region close to the source region. The second oxide layers are located at a side in the first region close to the drain region.
1 . A voltage-sustaining layer for semiconductors, comprising:
a source region of a first conductive type;
a drain region of a second conductive type, wherein the second conductive type is opposite to the first conductive type;
a first region of the first conductive type;
a second region of the second conductive type;
N first oxide layers spaced apart from one another; and
K second oxide layers spaced apart from one another;
wherein the second region is located above the drain region; the first region is located above the drain region and at one side of the second region; the source region is located above the first region and the second region; the N first oxide layers are located in the second region and spaced apart from the first region, the source region, and the drain region; the K second oxide layers are located in the first region and spaced apart from the second region, the source region, and the drain region; and N and K are independently a positive integer greater than 1.
2 . The voltage-sustaining layer of claim 1 , wherein a tapered superjunction with a trench angle is formed between the second region and the first region.
3 . The voltage-sustaining layer of claim 1 , wherein an oxide insulator with a trench angle is provided between the second region and the first region.
4 . The voltage-sustaining layer of claim 1 , wherein the second region and the first region each have a vertical varying doping profile.
5 . The voltage-sustaining layer of claim 3 , wherein the second region and the first region each have a vertical varying doping profile.
6 . The voltage-sustaining layer of claim 1 , wherein a buffer layer is provided between the drain region and the second region and between the drain region and the first region, and the buffer layer is made of the second conductive type.
7 . The voltage-sustaining layer of claim 3 , wherein a buffer layer is provided between the drain region and the second region and between the drain region and the first region, and the buffer layer is made of the second conductive type.
8 . The voltage-sustaining layer of claim 6 , wherein a plurality of third oxide layers are provided at the first side of the buffer layer, horizontal to the interface between the buffer layer and the drain layer, and a plurality of fourth oxide layers are provided at the second side of the buffer layer, horizontal to the interface between the buffer layer and the drain layer.
9 . The voltage-sustaining layer of claim 1 , wherein each of the N first oxide layers is separated from a vertical boundary of the second region; and each of the K second oxide layers is separated from a vertical boundary of the first region.
10 . The voltage-sustaining layer of claim 3 , wherein each of the N first oxide layers is separated from a vertical boundary of the second region; and each of the K second oxide layers is separated from a vertical boundary of the first region.
11 . The voltage-sustaining layer of claim 1 , wherein the N first oxide layers and the K second oxide layers each have a thickness of 0.1~1 μm.
12 . A superjunction structure, wherein the superjunction structure is achieved from the voltage-sustaining layer of claim 1 by interdigitated layout, hexagonal layout or square layout.
13 . The voltage-sustaining layer of claim 1 , wherein the N first oxide layers are closer to the source region than the drain region.
14 . The voltage-sustaining layer of claim 1 , wherein the K second oxide layers are closer to the drain region than the source region.
15 . The voltage-sustaining layer of claim 13 , wherein the K second oxide layers are closer to the drain region than the source region.