Semiconductor device
View Patent ↗A semiconductor device manufactured by forming a plurality of first trenches in each of which a trench gate is formed, in an epitaxial layer of a first conductivity type; implanting an impurity of a second conductivity type into a part beneath each of the first trenches to form a first column region; and implanting an impurity of the second conductivity type into a part beneath a base region formed between the first trenches to form a second column region. The first and second column regions are formed with an impurity concentration such that a total depletion charge in the regions is substantially equal to a depletion charge in the epitaxial layer.
1. A method of manufacturing a semiconductor device, comprising:
forming a plurality of first trenches in each of which a trench gate is to be formed, in an epitaxial layer of a first conductivity type;
implanting an impurity of a second conductivity type into a part beneath each of the first trenches to form a first column region; and
implanting an impurity of the second conductivity type into a part beneath a base region formed between the first trenches to form a second column region,
wherein the first and the second column regions are formed with an impurity concentration such that a total depletion charge in the first and the second column regions is substantially equal to a depletion charge in the epitaxial layer.
2. The method of manufacturing a semiconductor device of claim 1 , wherein the second column region is formed beneath a second trench formed in a surface of the base region.
3. A method of manufacturing a semiconductor device, comprising:
forming a first trench in a semiconductor layer of a first conductivity type;
implanting an impurity of a second conductivity type in the semiconductor layer through the first trench to form a first column region;
forming a second trench in the semiconductor layer;
implanting an impurity of the second conductivity type in the semiconductor layer through the second trench to form a second column region; and
filling a conductive material in the second trench.
4. The method of manufacturing a semiconductor device of claim 3 , wherein the first column region is separate from the first trench.
5. The method of manufacturing a semiconductor device of claim 3 , wherein the first column region has a continuous form.
6. The method of manufacturing a semiconductor device of claim 3 , wherein the first column region comprises a plurality of separate regions.
7. The method of manufacturing a semiconductor device of claim 3 , further comprising a base region of the second conductivity type formed in the semiconductor layer and a source region of the first conductivity type formed in the base region.
8. The method of manufacturing a semiconductor device of claim 7 , wherein the second column region is continuous with the base region.
9. The method of manufacturing a semiconductor device of claim 7 , wherein the second column region is separate from the base region.
10. The method of manufacturing a semiconductor device of claim 3 , wherein the second column region has a continuous form.
11. The method of manufacturing a semiconductor device of claim 3 , wherein the second column region comprises a plurality of separate regions.
12. The method of manufacturing a semiconductor device of claim 3 , wherein each of the first and the second column regions has a continuous form.
13. The method of manufacturing a semiconductor device of claim 3 , wherein each of the first and the second column regions comprises a plurality of separate regions.
14. The method of manufacturing a semiconductor device of claim 7 , wherein the conductive material is connected to both the base region and the source region.
15. The method of manufacturing a semiconductor device of claim 1 , further comprising forming said base region above said epitaxial layer of said first conductivity type.
16. The method of manufacturing a semiconductor device of claim 15 , further comprising orienting vertically said first and second column regions relative to a substrate.
17. The method of manufacturing a semiconductor device of claim 2 , further comprising locating the second trench located between said first trenches with trench gates, the base layer being exposed at a location of the second trench, and a source electrode being located thereon.
18. The method of manufacturing a semiconductor device of claim 3 , further comprising forming said base region above said semiconductor layer of said first conductivity type.
19. The method of manufacturing a semiconductor device of claim 18 , further comprising orienting vertically said first and second column regions.
20. The method of manufacturing a semiconductor device of claim 6 , further comprising locating the second trench between said separate regions of said first column region, a base layer being exposed at the location of the second trench, and a source electrode being located thereon.