Semiconductor device
The present examples relate to a semiconductor device used in an electric device or high voltage device. The present examples improve R sp by minimizing drift region resistance by satisfying breakdown voltage by improving the structure of a drift region through which current flows in a semiconductor device to provide optimal results. Moreover, a high frequency application achieves useful results by reducing a gate charge Q g for an identical device pitch to that of an alternative technology.
1. A semiconductor device comprising:
a first deep well region and a second deep well region abutting against each other and disposed in a semiconductor substrate;
a first conductivity type well region disposed in the first deep well region;
a second conductivity type well region disposed in the second deep well region and spaced apart from the first conductivity type well region;
a second conductivity type source region disposed in the first conductivity type well region;
a second conductivity type drain region disposed in the second conductivity type well region;
a second conductivity type buried layer in direct contact with and located below the first deep well region and the second deep well region;
a gate insulating layer formed on the first deep well region and the second deep well region;
a gate electrode disposed on the gate insulating layer;
first and second spacers disposed on sidewalls of the gate electrode;
a first deep trench isolation disposed to abut the first deep well region and the second conductivity type buried layer, and spaced apart from the first conductivity type well region formed in the first deep well region; and
a second deep trench isolation disposed to abut the second deep well region and the second conductivity type buried layer, and spaced apart from the second conductivity type well region formed in the second deep well region,
wherein the second deep well region is in direct contact with the second deep trench isolation, the second conductivity type buried layer, the second conductivity type well region and the gate insulating layer.
2. The semiconductor device of claim 1 , wherein the first deep trench isolation and the second deep trench isolation are formed to surround the first conductivity type well region, the second conductivity type well region, the first deep well region, the second deep well region, and the second conductivity type buried layer, respectively.
3. The semiconductor device of claim 1 , further comprising:
a first shallow trench isolation formed in the first deep well region; and
a second shallow trench isolation formed in the second deep well region,
wherein the first shallow trench isolation is in contact with the first conductivity type well region,
wherein a depth of the second conductivity type well region is shallower than the second deep well region but deeper than each of the first and second shallow trench isolations, and
wherein the second shallow trench isolation is in contact with the second conductivity type well region and the second conductivity type drain region.
4. The semiconductor device of claim 1 , wherein the first deep trench isolation and the second deep trench isolation are in contact with the second conductivity type buried layer and are formed deeper than the second conductivity type buried layer.
5. The semiconductor device of claim 1 , wherein the gate insulating layer comprises a first gate insulating layer having a first thickness and a second gate insulating layer having a second thickness that is thicker than the first gate insulating layer.
6. The semiconductor device of claim 5 , wherein the second gate insulating layer is disposed between the drain region and the first gate insulating layer disposed adjacent to the source region.
7. The semiconductor device of claim 5 , wherein the second gate insulating layer is disposed spaced apart from the second conductivity type well region.
8. The semiconductor device of claim 2 , wherein the second deep well region extends from a region below the second shallow trench isolation to a region below the gate insulating layer.
9. The semiconductor device of claim 5 , wherein the first gate insulating layer overlaps with the first deep well region and the second deep well region.
10. The semiconductor device of claim 1 , wherein the edge of the second conductivity type drain region is horizontally spaced apart from each edge of the second conductivity type well region and the second deep well region.
11. The semiconductor device of claim 1 , wherein the first deep well region in which the first conductivity type well region is formed is in direct contact with the first deep trench isolation, the second conductivity type buried layer, the first conductivity type well region and the gate insulating layer.
12. The semiconductor device of claim 1 , wherein the first conductivity type well region formed in the first deep well region overlaps the gate electrode and the first spacer,
wherein the second conductivity type well region formed in the second deep well region is spaced apart from the gate insulating layer and the second spacer, and
wherein an edge of the second conductivity type drain region is spaced apart from an edge of the second conductivity type well region formed in the second deep well region.
13. The semiconductor device of claim 1 , wherein the first conductivity type well region formed in the first deep well region has a horizontal maximum length greater than that of the second conductivity type well region formed in the second deep well region.
14. The semiconductor device of claim 1 , wherein the first conductivity type well region formed in the first deep well region is in direct contact with the second conductivity type source region and a first conductivity type pickup region.
15. A semiconductor device comprising:
a first deep well region and a second deep well region abutting against each other and disposed in a semiconductor substrate;
a first conductivity type well region disposed in the first deep well region;
a second conductivity type well region disposed in the second deep well region and spaced apart from the first conductivity type well region;
a second conductivity type source region disposed in the first conductivity type well region;
a second conductivity type drain region disposed in the second conductivity type well region;
a second conductivity type buried layer in direct contact with and located below the first deep well region and the second deep well region;
a gate insulating layer formed on the first deep well region and the second deep well region, and spaced apart from the second conductivity type well region;
a gate electrode disposed on the gate insulating layer;
a first deep trench isolation disposed to abut the first deep well region and the second conductivity type buried layer, and spaced apart from the first conductivity type well region formed in the first deep well region; and
a second deep trench isolation disposed to abut the second deep well region and the second conductivity type buried layer, and spaced apart from the second conductivity type well region formed in the second deep well region,
wherein the first deep well region is in direct contact with the first deep trench isolation, the second conductivity type buried layer, the first conductivity type well region and the gate insulating layer.
16. The semiconductor device of claim 15 , further comprising:
a first shallow trench isolation formed in the first deep well region;
a second shallow trench isolation formed in the second deep well region;
a third shallow trench isolation separating the second conductivity type source region and a first conductivity type pickup region disposed in the first conductivity type well region; and
a fourth shallow trench isolation overlapped with the gate electrode and separating the gate electrode and the second conductivity type drain region,
wherein a depth of the second conductivity type well region is shallower than the second deep well region but deeper than each shallow trench isolation,
wherein the first conductivity type well region encloses the first conductivity type pickup region, the second conductivity type source region and the third shallow trench isolation, and
wherein the second conductivity type well region is in contact with the second shallow trench isolation and the fourth shallow trench isolation.
17. The semiconductor device of claim 15 , wherein the first deep trench isolation and the second deep trench isolation are in contact with the second conductivity type buried layer and are formed deeper than the second conductivity type buried layer.
18. The semiconductor device of claim 15 ,
wherein the second deep well region in which the second conductivity type well region is formed is in direct contact with the second deep trench isolation, the second conductivity type buried layer, the second conductivity type well region and the gate insulating layer.
19. The semiconductor device of claim 15 , wherein a depth of the first deep trench isolation is greater than a total depth of the first deep well region and the second conductivity type buried layer.
20. The semiconductor device of claim 15 , wherein the first deep trench isolation and the second deep trench isolation are disposed to surround the first conductivity type well region, the second conductivity type well region, the first deep well region, the second deep well region and the second conductivity type buried layer.