1. A method of making a semiconductor device, comprising:
providing a substrate;
forming a trench partially through the substrate;
forming a vertical drift region along a sidewall of the trench;
depositing an insulating material within the trench;
forming a channel region along the sidewall of the trench above the insulating material;
forming a gate structure within the trench self-aligned to the channel region; and
forming a source region in a first surface of the substrate contacting the channel region.
2. The method of claim 1, wherein providing the substrate includes:
forming a drain region in the substrate as a second surface of the substrate opposite the first surface of the substrate; and
forming an epitaxial region in the substrate over the drain region.
3. The method of claim 2, further including, wherein forming the vertical drift region includes forming a plurality of doped regions between the source region and drain region.
4. The method of claim 2, further including:
forming an insulating layer over the first surface of the substrate;
forming a first conductive layer over the insulating layer electrically connected to the source region; and
forming a second conductive layer over the second surface of the substrate electrically connected to the drain region.
5. The method of claim 1, wherein forming the gate structure includes:
forming an insulating layer along the sidewall of the trench adjacent to the channel region; and
forming a polysilicon layer within the trench over the insulating layer.
6. The method of claim 1, wherein the channel region is separated from the insulating material.
7. A method of making a semiconductor device, comprising:
providing a substrate;
forming a trench in the substrate;
forming a vertical drift region along a sidewall of the trench;
depositing an insulating material within the trench;
forming a channel region along the sidewall of the trench;
forming a gate structure within the trench over the insulating material and adjacent to the channel region; and
forming a source region in a first surface of the substrate.
8. The method of claim 7, wherein providing the substrate includes:
forming a drain region in the substrate as a second surface of the substrate opposite the first surface of the substrate; and
forming an epitaxial region in the substrate over the drain region.
9. The method of claim 8, further including:
forming an insulating layer over the first surface of the substrate;
forming a first conductive layer over the insulating layer electrically connected to the source region; and
forming a second conductive layer over the second surface of the substrate electrically connected to the drain region.
10. The method of claim 7, wherein forming the gate structure includes:
forming an insulating layer along the sidewall of the trench adjacent to the channel region; and
forming a polysilicon layer within the trench over the insulating layer.
11. The method of claim 7, wherein the channel region is separated from the insulating material.
12. The method of claim 7, further including forming an ohmic contact region overlapping the source region and epitaxial region.
13. The method of claim 7, further including:
forming an insulating layer over the first surface of the substrate;
forming a first conductive layer through the insulating layer electrically connected to the source region; and
forming a second conductive layer through the insulating layer electrically connected to the gate structure.
14. A method of making a semiconductor device, comprising:
providing a substrate;
forming a trench in the substrate;
forming a vertical drift region along a sidewall of the trench;
forming a channel region along the sidewall of the trench;
forming a gate structure within the trench adjacent to the channel region; and
forming a source region in a first surface of the substrate.
15. The method of claim 14, further including depositing an insulating material within the trench prior to forming the gate structure.
16. The method of claim 15, wherein the channel region is separated from the insulating material.
17. The method of claim 14, wherein providing the substrate includes:
forming a drain region in the substrate as a second surface of the substrate opposite the first surface of the substrate; and
forming an epitaxial region in the substrate over the drain region.
18. The method of claim 17, further including:
forming an insulating layer over the first surface of the substrate;
forming a first conductive layer over the insulating layer electrically connected to the source region; and
forming a second conductive layer over the second surface of the substrate electrically connected to the drain region.
19. The method of claim 14, further including forming the vertical drift region with an angled implant into a sidewall of the trench.
20. A semiconductor device, comprising:
a substrate;
a trench formed in the substrate;
a vertical drift region formed along a sidewall of the trench;
a channel region formed along the sidewall of the trench;
a gate structure formed within the trench adjacent to the channel region; and
a source region formed in a first surface of the substrate.
21. The semiconductor device of claim 20, further including an insulating material deposited within the trench.
22. The semiconductor device of claim 21, wherein the channel region is separated from the insulating material.
23. The semiconductor device of claim 20, wherein the substrate includes:
a drain region formed in the substrate as a second surface of the substrate opposite the first surface of the substrate; and
an epitaxial region formed in the substrate over the drain region.
24. The semiconductor device of claim 20, further including:
an insulating layer formed over the first surface of the substrate;
a first conductive layer formed over the insulating layer electrically connected to the source region; and
a second conductive layer formed over the second surface of the substrate electrically connected to the drain region.
25. The semiconductor device of claim 20, wherein the gate structure includes:
an insulating layer formed along the sidewall of the trench adjacent to the channel region; and
a polysilicon layer formed within the trench over the insulating layer.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1-7. (canceled)
8. A device for monitoring a conveyor belt, the device comprising:
the conveyor belt having an object to be detected;
a shaft having a flat surface facing the conveyor belt;
a guide roller rotatively supported around the shaft via a bearing to form a space within the guide roller; and
a sensor on the flat surface of the shaft to face the conveyor belt to detect variation of the object of the conveyor belt.
9. The device of claim 8, further comprising a cable from the sensor, a cavity being formed at an axial end of the shaft, a through hole being formed through a circumference of the shaft, the cable passing through the through hole and the cavity and being pulled out of the axial end of the shaft.
10. The device of claim 8 wherein a plurality of shafts and a plurality of guide rollers are provided, the sensor being provided on at least one of the plurality of shafts.
11. The device of claim 8 wherein a plurality of shafts and a plurality of guide rollers are provided along width of the conveyor belt, the sensor being provided on the shaft in the space of the guide roller.
12. The device of claim 8 wherein the guide roller always contacts the conveyor belt.
13. The device of claim 8 wherein the object of the conveyor belt comprises a magnet, while the sensor comprises a magnetic sensor detecting magnetic strength from the object.
14. The device of claim 8 further comprising a closure and a bracket, the closure horizontally engaging with the shaft at an end and having a noncircular cross section, the closure fitting in a noncircular axial hole of the bracket to allow the sensor on the shaft to always face a surface of the conveyor belt on which materials are not conveyed.