1. A semiconductor device, comprising:
a first compound semiconductor material;
a second compound semiconductor material on the first compound semiconductor material, the second compound semiconductor material comprising a different material than the first compound semiconductor material such that the first compound semiconductor material has a two-dimensional electron gas (2DEG); and
a buried field plate disposed in the first compound semiconductor material and electrically connected to a terminal of the semiconductor device, the 2DEG being interposed between the buried field plate and the second compound semiconductor material.
2. The semiconductor device of claim 1, wherein the buried field plate comprises the same material as the second compound semiconductor material.
3. The semiconductor device of claim 2, wherein the buried field plate and the second compound semiconductor material each comprise AlGaN.
4. The semiconductor device of claim 1, wherein the buried field plate comprises InGaN.
5. The semiconductor device of claim 1, wherein the buried field plate comprises a more highly doped region of the first compound semiconductor material surrounded by a less highly doped region of the first compound semiconductor material.
6. The semiconductor device of claim 1, further comprising:
a gate region over the 2DEG;
a source region extending through the second compound semiconductor material to the first compound semiconductor material and in contact with the buried field plate; and
a drain region extending through the second compound semiconductor material to the first compound semiconductor material and spaced apart from the source region and the buried field plate.
7. The semiconductor device of claim 6, wherein a distance between the buried field plate and the 2DEG is greater than a distance between the gate region and the 2DEG.
8. The semiconductor device of claim 6, wherein the buried field plate extends laterally from the source region toward the drain region further than the gate region.
9. The semiconductor device of claim 6, wherein the buried field plate and the source region comprise doped regions of the same doping type.
10. The semiconductor device of claim 6, further comprising at least one additional buried field plate disposed in the first compound semiconductor material below the 2DEG and in contact with the source region, adjacent ones of the buried field plates being spaced apart from one another by a region of the first compound semiconductor material.
11. The semiconductor device of claim 10, wherein the source region extends deeper into the first compound semiconductor material than the drain region.
12. The semiconductor device of claim 10, wherein a second one of the buried field plates is spaced further away from the second compound semiconductor material than a first one of the buried field plates, and laterally extends further from the source region toward the drain region than the first one of the buried field plates.
13. The semiconductor device of claim 6, wherein a distance between the buried field plate and the 2DEG increases in a direction laterally extending from the source region to the drain region.
14. The semiconductor device of claim 1, further comprising a second 2DEG in the first compound semiconductor material and spaced further apart from the second compound semiconductor material than the first 2DEG, and wherein the buried field plate is interposed between the first and second 2DEGs.
15. The semiconductor device of claim 14, wherein the first 2DEG extends laterally from a source region of the semiconductor device to a drain region of the semiconductor device and forms a channel of the semiconductor device, and the second 2DEG extends laterally from the source region toward the drain region and terminates before reaching the drain region.
16. The semiconductor device of claim 1, further comprising a two-dimensional hole gas (2DHG) in the first compound semiconductor material and spaced further apart from the second compound semiconductor material than the 2DEG, and wherein the buried field plate is interposed between the 2DEG and the 2DHG.
17. A semiconductor device, comprising:
a first III-V semiconductor material;
a second III-V semiconductor material on the first III-V semiconductor material, the second III-V semiconductor material comprising a different material than the first III-V semiconductor material such that the first III-V semiconductor material has a two-dimensional electron gas (2DEG);
a gate region on the second III-V semiconductor material with the second III-V semiconductor material interposed between the 2DEG and the gate region;
a source region extending through the second III-V semiconductor material to the first III-V semiconductor material;
a drain region extending through the second III-V semiconductor material to the first III-V semiconductor material and spaced apart from the source region; and
a metallization on a side of the first III-V semiconductor material facing away from the second III-V semiconductor material, the first III-V semiconductor material having a thickness which increases in a direction extending laterally from the source region to the drain region.
18. The semiconductor device of claim 17, wherein the thickness of the first III-V semiconductor material increases stepwise in the direction extending laterally from the source region to the drain region.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A lamp comprising:
an outer shell with heat conductivity which includes a light source support, and a heat radiating surface exposed to the outside of the outer shell, and the light source support (113) formed integrally with the heat radiating surface;
a base which is provided in the outer shell;
a heat generating light source which is supported on the light source support, and thermally connected to the light source support;
a cover which covers the light source; and
a heat radiating path provided on the outer shell, the heat radiating path continuing in the axial direction of the outer shell.
2. The lamp of claim 1, wherein the heat radiating surface is exposed to the heat radiating path.
3. The lamp of claim 2, wherein the outer shell has a plurality of heat radiating fins protruding from the heat radiating surface.
4. The lamp of claim 1, wherein the heat radiating path has a plurality of areas arranged with an interval in the circumferential direction of the outer shell.
5. The lamp of claim 1, wherein the outer shell has a receptacle provided inside the heat radiating surface, and the receptacle contains a lighting circuit to light the light source.
6. The lamp of claim 5, wherein the receptacle is covered by an electrical insulating layer.
7. The lamp of claim 6, wherein the outer shell has an end wall partitioning the light source support and the receptacle, and a heat shielding gap is provided between the end wall and the electrical insulating layer.
8. The lamp of claim 1, wherein the light source is a light-emitting diode.