1. A magnetic braking motor system comprising:
a motor comprising:
a motor enclosure; and
a motor shaft rotatably mounted with respect to the motor enclosure; and
a magnetic brake assembly comprising:
a rotating magnetic element mounted with respect to the motor shaft; and
a stationary magnetic element mounted with respect to the motor enclosure, wherein a magnetic field is provided between the rotating magnetic element and the stationary magnetic element.
2. The magnetic braking motor system of claim 1, wherein the motor has a rotational strength when the motor is turned on and wherein the motor rotational strength is larger than a strength of the magnetic field.
3. The magnetic braking motor system of claim 1, wherein at least one of the rotating magnetic element and the stationary magnetic element comprises at least one magnet portion.
4. The magnetic braking motor system of claim 3, wherein the at least one magnet portion is a permanent magnet.
5. The magnetic braking motor system of claim 4, wherein the permanent magnet is a rare earth permanent magnet.
6. The magnetic braking motor system of claim 3, wherein magnet portions are mounted with respect to the motor enclosure in a spaced-apart configuration so that a spacing between adjacent magnet portions is approximately equal.
7. The magnetic braking motor system of claim 1, wherein at least a portion of the rotating magnetic element is fabricated from a ferrous material and at least a portion of the stationary magnetic element is a permanent magnet.
8. The magnetic braking motor system of claim 7, wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein a quantity of the at least one leg is equal to a quantity of the at least one magnet portion.
9. The magnetic braking motor system of claim 7, wherein the motor further comprises an armature mounted with respect motor shaft and wherein an interaction between the armature and the stationary magnetic element causes the motor shaft to rotate with respect to the motor enclosure.
10. The magnetic braking motor system of claim 7, wherein the rotating magnetic element is fabricated from a plurality of pieces and wherein each of the pieces have a similar shape.
11. The magnetic braking motor system of claim 7, wherein the rotating magnetic element completes a magnetic field in the stationary magnetic element and the motor enclosure.
12. The magnetic braking motor system of claim 1, wherein at least a portion of the rotating magnetic element is a permanent magnet and at least a portion of the stationary magnetic element is fabricated from a ferrous material.
13. The magnetic braking motor system of claim 12, wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein at least a portion of each leg is the permanent magnet.
14. The magnetic braking motor system of claim 1, wherein the magnetic brake assembly is separate from the motor.
15. The magnetic braking motor system of claim 1, and further comprising a torque multiplying mechanism operably attached to at least one of the motor and the magnetic brake assembly, wherein the torque multiplying mechanism has an input shaft and an output shaft and wherein a torque provided by the input shaft is different than a torque provided by the output shaft.
16. The magnetic braking motor system of claim 1, wherein the magnetic brake assembly functions as a slip clutch for the motor.
17. A magnetic braking motor system comprising:
a motor comprising:
a motor enclosure; and
a motor shaft rotatably mounted with respect to the motor enclosure;
a torque multiplying mechanism having an input shaft and an output shaft, wherein a torque provided by the input shaft is different than a torque provided by the output shaft; and
a magnetic brake assembly comprising:
a rotating magnetic element mounted with respect to the motor shaft and the input shaft; and
a stationary magnetic element mounted with respect to the motor enclosure, wherein a magnetic field is provided between the rotating magnetic element and the stationary magnetic element.
18. The magnetic braking motor system of claim 17, wherein the motor has a rotational strength when the motor is turned on and wherein the motor rotational strength is larger than a strength of the magnetic field.
19. The magnetic braking motor system of claim 17, wherein at least one of the rotating magnetic element and the stationary magnetic element comprises at least one magnet portion.
20. The magnetic braking motor system of claim 19, wherein the at least one magnet portion is a permanent magnet.
21. The magnetic braking motor system of claim 17, wherein at least a portion of the rotating magnetic element is fabricated from a ferrous material and at least a portion of the stationary magnetic element is a permanent magnet, wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein a quantity of the at least one leg is equal to a quantity of the at least one magnet portion.
22. The magnetic braking motor system of claim 17, wherein at least a portion of the rotating magnetic element is a permanent magnet and at least a portion of the stationary magnetic element is fabricated from a ferrous material and wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein at least a portion of each leg is the permanent magnet.
23. The magnetic braking motor system of claim 17, wherein the torque multiplying mechanism has a ratio of between about 50:1 and about 250:1.
24. A motorized cover system for a vehicle having an upwardly directed opening, wherein the motorized cover system comprises:
a cover material that is capable of covering at least a portion of the upwardly directed opening;
a cover material shaft operably attached to the cover material, wherein the cover material is rolled onto the cover material shaft when moving from an extended configuration to a retracted configuration;
a motor comprising:
a motor enclosure; and
a motor shaft rotatably mounted with respect to the motor enclosure, wherein the motor shaft is operably attached to the cover material shaft; and
a magnetic brake assembly comprising:
a rotating magnetic element mounted with respect to the motor shaft; and
a stationary magnetic element mounted with respect to the motor enclosure, wherein a magnetic field is provided between the rotating magnetic element and the stationary magnetic element.
25. The motorized cover system of claim 24, and further comprising an arm assembly that is operably attached the motor to the vehicle.
26. The motorized cover system of claim 24, wherein the motor has a rotational strength when the motor is turned on and wherein the motor rotational strength is larger than a strength of the magnetic field.
27. The motorized cover system of claim 24, wherein at least one of the rotating magnetic element and the stationary magnetic element comprises at least one magnet portion.
28. The motorized cover system of claim 27, wherein the at least one magnet portion is a permanent magnet.
29. The motorized cover system of claim 24, wherein at least a portion of the rotating magnetic element is fabricated from a ferrous material and at least a portion of the stationary magnetic element is a permanent magnet, wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein a quantity of the at least one leg is equal to a quantity of the at least one magnet portion.
30. The motorized cover system of claim 24, wherein at least a portion of the rotating magnetic element is a permanent magnet and at least a portion of the stationary magnetic element is fabricated from a ferrous material and wherein the rotating magnetic element comprises a central region and at least one leg that extends from the central region and wherein at least a portion of each leg is the permanent magnet.
31. The motorized cover system of claim 24, and further comprising a torque multiplying mechanism operably attached to at least one of the motor and the magnetic brake assembly, wherein the torque multiplying mechanism has an input shaft and an output shaft and wherein a torque provided by the input shaft is different than a torque provided by the output shaft.
32. A method of using a magnetic brake comprising:
providing a motor comprising a motor enclosure in which a motor shaft is rotatably mounted; and
preventing rotation of the motor shaft with respect to the motor enclosure with a magnetic brake assembly, wherein the magnetic brake assembly comprises a rotating magnetic element and a stationary magnetic element, wherein the rotating magnetic element is mounted with respect to the motor shaft, wherein the stationary magnetic element is mounted with respect to the motor enclosure and wherein a magnetic field is provided between the rotating magnetic element and the stationary magnetic element.
33. The method of claim 32, wherein the motor has a rotational strength when the motor is turned on and wherein the motor rotational strength is larger than a strength of the magnetic field.
34. The method of claim 32, wherein at least one of the rotating magnetic element and the stationary magnetic element comprises at least one magnet portion and wherein the at least one magnet portion is a permanent magnet.
35. The method of claim 34, and further comprising:
mounting the at least one magnet portion with respect to the motor enclosure;
forming the rotating magnetic element with a central region and at least one leg that extends from the central region; and
providing the at least one leg with a quantity is equal to a quantity of the at least one magnet portion.
36. The method of claim 34, and further comprising:
mounting the at least one magnet portion with respect to the motor shaft; and
fabricating at least a portion of the motor enclosure from a ferrous material.
37. The method of claim 32, and further comprising operably attaching a torque multiplying mechanism to at least one of the motor and the magnetic brake assembly, wherein the torque multiplying mechanism has an input shaft and an output shaft and wherein a torque provided by the input shaft is different than a torque provided by the output shaft.
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 method for forming a power device, comprising:
forming an epitaxial layer on a substrate material;
selectively removing a portion of the epitaxial layer to form a column extending from the substrate material, the column having a sidewall;
forming an insulation material on the sidewall of the column; and
diffusing a dopant into the sidewall of the column via the insulation material.
2. The method of claim 1 wherein:
forming an epitaxial layer includes forming an n-type epitaxial layer on an n-type substrate material;
the insulating material is a first insulation material having a first thickness;
the method further includes forming a second insulation material onto an exposed surface of the column, the second insulation material having a second thickness greater than the first thickness, wherein the first and second insulation materials include at least one of silicon dioxide, spin-on glass, and flowable oxide;
selectively removing a portion of the epitaxial layer includes:
depositing a photoresist onto the second insulation material;
patterning the deposited photoresist to form an opening in the photoresist;
removing material from the second insulation material and the epitaxial layer via the opening; and
diffusing a dopant includes:
depositing a polysilicon material on the first and second insulation materials, the polysilicon being doped with a p-type dopant; and
diffusing the p-type dopant of the polysilicon into the sidewall of the column via the first insulation material while the second insulation material prevents the p-type dopant from diffusing into the surface of the column.
3. The method of claim 1 wherein forming an insulation material includes forming silicon dioxide on the sidewall of the column via thermal oxidation.
4. The method of claim 1 wherein forming an insulation material includes forming silicon dioxide on the sidewall of the column via thermal oxidation, the silicon dioxide having a thickness of about 50 to about 150 Angstroms.
5. The method of claim 1 wherein diffusing a dopant includes:
depositing a doping material on the insulation material, the doping material carrying a dopant; and
diffusing the dopant carried by the doping material into the sidewall of the column via the insulation material.
6. The method of claim 1 wherein diffusing a dopant includes:
depositing a polysilicon material on the insulation material, the polysilicon material being doped with a p-type dopant; and
diffusing the p-type dopant carried by the polysilicon material into the sidewall of the column via the insulation material.
7. The method of claim 1 wherein:
the insulating material is a first insulation material;
the method further includes forming a second insulation material onto an exposed surface of the column;
diffusing a dopant includes:
depositing a doping material on the insulation material, the doping material carrying a dopant; and
diffusing the dopant carried by the doping material into the sidewall of the column via the first insulation material while the second insulation material prevents the dopant from diffusing into the surface of the column.
8. The method of claim 1 wherein:
the insulating material is a first insulation material;
the method further includes forming a second insulation material onto an exposed surface of the column;
diffusing a dopant includes:
depositing a polysilicon material on the insulation material, the polysilicon material being doped with a p-type dopant; and
diffusing the p-type dopant carried by the polysilicon material into the sidewall of the column via the first insulation material while the second insulation material prevents the p-type dopant from diffusing into the surface of the column.
9. The method of claim 1 wherein:
the insulating material is a first insulation material;
the method further includes forming a second insulation material onto an exposed surface of the column;
diffusing a dopant includes:
depositing a polysilicon material on the insulation material, the polysilicon material being doped with a p-type dopant;
diffusing a first portion of the p-type dopant into the sidewall of the column and a second portion of the p-type dopant into the substrate material via the first insulation material while the second insulation material prevents the p-type dopant from diffusing into the surface of the column; and
the method further includes selectively etching the substrate material to remove at least a part of the second portion of the p-type dopant.
10. The method of claim 1 wherein forming an insulation material includes:
forming a first portion of the insulation material onto the sidewall of the column and a second portion onto a surface of the substrate material;
the method further includes:
depositing a barrier material onto the insulation material;
selectively removing a portion of the barrier material such that the second portion of the insulation material is exposed;
the method further includes increasing a thickness of the second portion of the insulation material;
diffusing a dopant includes diffusing the dopant into the sidewall of the column via the first portion of the insulation material while the second portion of the insulation material prevents the dopant from diffusing into the substrate material.
11. A method for forming a power device, comprising:
forming an epitaxial layer on a substrate material;
forming a trench in the epitaxial layer, the trench having a first sidewall, a second sidewall, and a bottom between the first and second sidewalls;
forming an insulation material on at least one of the first and second sidewalls of the trench; and
diffusing a dopant into the epitaxial layer via at least one of the first and second sidewalls of the trench via the insulation material.
12. The method of claim 11 wherein forming an insulation material includes forming at least one of silicon dioxide, spin-on glass, and flowable oxide on the first and second sidewalls.
13. The method of claim 11 wherein forming an insulation material includes forming at least one of silicon dioxide, spin-on glass, and flowable oxide on the first and second sidewalls, the insulation material having a thickness of about 50 to about 150 Angstroms.
14. The method of claim 11 wherein diffusing a dopant includes:
depositing a doping material on the insulation material, the doping material carrying a dopant; and
diffusing the dopant carried by the doping material into the epitaxial layer via the insulation material.
15. The method of claim 11 wherein diffusing a dopant includes:
depositing a polysilicon material on the insulation material, the polysilicon material being doped with a p-type dopant; and
diffusing the p-type dopant carried by the polysilicon material into epitaxial layer via the insulation material.
16. The method of claim 11 wherein:
the insulating material is a first insulation material;
the epitaxial layer has a first surface in direct contact with the substrate material;
the epitaxial layer has a second surface opposite the first surface;
the method further includes forming a second insulation material onto the second surface of the epitaxial layer;
diffusing a dopant includes:
depositing a doping material on the first and second insulation materials, the doping material carrying a dopant; and
diffusing the dopant carried by the doping material into the epitaxial layer via the first insulation material while the second insulation material prevents the dopant from diffusing into the second surface of the epitaxial layer.
17. The method of claim 1 wherein:
the insulating material is a first insulation material;
the epitaxial layer has a first surface in direct contact with the substrate material;
the epitaxial layer has a second surface opposite the first surface;
the method further includes forming a second insulation material onto the second surface of the epitaxial layer;
diffusing a dopant includes:
depositing a polysilicon material on the first and second insulation materials, the polysilicon material being doped with a p-type dopant; and
diffusing the p-type dopant carried by the polysilicon material into the epitaxial layer via the first insulation material while the second insulation material prevents the p-type dopant from diffusing into the second surface of the epitaxial layer.
18. A method for forming a power device, comprising:
forming an n-type column extending from a substrate material, the column having a first surface in direct contact with the substrate material, a second surface opposite the first surface, and a sidewall between the first and second surfaces;
introducing an insulation material onto the sidewall of the column; and
diffusing a dopant into the column via the introduced insulation material.
19. The method of claim 18 wherein:
the insulation material is a first insulation material;
the method further includes introducing a second insulation material onto the second surface of the column; and
the second insulation material having a thickness greater than that of the first insulation material.
20. The method of claim 18 wherein:
the insulation material is a first insulation material with a first composition; and
the method further includes introducing a second insulation material onto the second surface of the column, the second insulation material having a second composition that is generally the same as that of the first insulation material.
21. The method of claim 18 wherein:
the insulation material is a first insulation material with a first composition; and
the method further includes introducing a second insulation material onto the second surface of the column, the second insulation material having a second composition that is different than that of the first insulation material.
22. The method of claim 18 wherein:
the insulation material is a first insulation material having a first rate of diffusion; and
the method further includes introducing a second insulation material onto the second surface of the column, the second insulation material having a second rate of diffusion lower than that of the first insulation material.
23. A vertical power device, comprising:
a drain comprising a first semiconductor material of a first conductivity type;
a drift region proximate to the drain, the drift region comprising an n-type pillar, a p-type pillar, and an insulating region juxtaposed with one another;
a body comprising a second semiconductor material of a second conductivity type opposite to the first conductivity type, the body being separated from the drain by the drift region; and
a source region of the first conductivity type in the body and spaced apart from the drift region.
24. The vertical power device of claim 23 wherein the p-type pillar has a substantially uniform width.
25. The vertical power device of claim 23, further comprising a buffer region between the drain and the drift region.
26. The vertical power device of claim 23, further comprising a buffer region between the drain and the drift region, wherein the buffer region includes a semiconductor material of the first conductivity type.
27. The vertical power device of claim 23, further comprising a buffer region between the drain and the drift region, wherein the buffer region includes a semiconductor material of the first conductivity type and has a doping concentration that is at least one order of magnitude less than a doping concentration of the drain.