SiC semiconductor device

Claim 2

A semiconductor device comprising: a semiconductor substrate which forms part of the conduction path; a drift region comprised of a material having a band gap that is greater than that of said semiconductor substrate and being disposed on the semiconductor substrate; an epitaxial layer of semiconductor material having a smaller band gap than said drift region and being disposed on the high band-gap materials; at least one electrode disposed on a top surface of said epitaxial layer; and at least another electrode disposed on a bottom surface of said semiconductor substrate.

Claim 3

The semiconductor device of claim 1, wherein the higher band-gap material forming said drift region is a low dielectric constant, high carrier mobility material.

Claim 4

The semiconductor device of claim 1, wherein the epitaxial layer of semiconductor material is about three μm thick.

Claim 5

The semiconductor device of claim 1, wherein the semiconductor substrate material is silicon.

Claim 6

The semiconductor device of claim 1, wherein the higher band-gap material forming said drift region is silicon carbide.

Claim 7

The semiconductor device of claim 1, wherein the epitaxial layer of semiconductor material is silicon.

Claim 8

The semiconductor device of claim 1, wherein the semiconductor substrate material is silicon, the higher band-gap material forming said drift region is silicon carbide, and the epitaxial layer of semiconductor material is silicon.

Claim 9

A MOSFET semiconductor device comprising: a doped semiconductor substrate which forms part of the conduction path; a doped drift region comprised of a material having a band gap that is greater than that of said semiconductor substrate and being disposed on the doped semiconductor substrate; a doped epitaxial layer of semiconductor material having a smaller band gap than said drift region and being disposed on the high band-gap material; at least one electrode disposed on a top surface of said epitaxial layer; and at least another electrode disposed on a bottom surface of said semiconductor substrate.

Claim 10

A MOSFET semiconductor device comprising: a doped semiconductor substrate which forms part of the conduction path; a doped drift region comprised of a material having a band gap that is greater than that of said semiconductor substrate and being disposed on the doped semiconductor substrate; a doped epitaxial layer of semiconductor material having a smaller band gap than said drift region and being disposed on the high band-gap material; at least one electrode disposed on a top surface of said epitaxial layer; and at least another electrode disposed on a bottom surface of said semiconductor substrate.

Claim 11

The MOSFET semiconductor device of claim 8, wherein the material forming said drift region is a low dielectric constant, high carrier mobility material.

Claim 12

The MOSFET semiconductor device of claim 8, wherein the epitaxial layer of semiconductor material is about, three μm thick.

Claim 13

The MOSFET semiconductor device of claim 8, wherein the semiconductor substrate material is silicon.

Claim 14

The MOSFET semiconductor device of claim 8, wherein the material forming said drift region is silicon carbide.

Claim 15

The MOSFET semiconductor device of claim 8, wherein the epitaxial layer of semiconductor material is silicon.

Claim 16

The MOSFET semiconductor device of claim 8, wherein the semiconductor substrate material is silicon, the material forming said drift region is silicon carbide, and the epitaxial layer of semiconductor material is silicon.

Claim 17

The semiconductor device of claim 8, wherein a high voltage supporting P body/N - drift junction is formed at the epitaxial layer/higher band-gap material hetero-junction.

Claim 18

The semiconductor device of claim 8, wherein a high voltage supporting P body/N - drift junction is formed in said epitaxial layer.

Claim 19

The semiconductor device of claim 8, wherein a high voltage supporting P body/N - drift junction is formed in said higher band-gap material.

Claim 20

The MOSFET semiconductor device of claim 8 wherein said doped semiconductor substrate and said doped drift region are of one conductivity type, and said device further comprises: a trench formed in at least said doped epitaxial layer; a thin insulating layer formed on the walls and bottom surface of said trench; a region of polysilicon formed in said trench such that said trench is filled, thereby forming a gate electrode; a body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in said top surface of said epitaxial layer at least adjoining said trench; a source region of said one conductivity type formed in the top surface of said epitaxial layer in at least a portion of said body region adjoining said trench and forming a channel region in said body region between said source region and said epitaxial layer; a source electrode formed on said top surface of said epitaxial layer; and a drain electrode formed on said bottom surface of said doped semiconductor substrate.

Claim 21

The MOSFET semiconductor device of claim 18 wherein said trench is further formed in said higher band-gap material, and a high voltage supporting body/drift junction is formed at the epitaxial layer/higher band-gap material hetero-junction.

Claim 22

The MOSFET semiconductor device of claim 18 wherein said trench is further formed in said higher band-gap material, and a high voltage supporting body/drift junction is formed in said higher band-gap material.

Claim 23

The MOSFET semiconductor device of claim 18 wherein said doped epitaxial layer is of said one conductivity type, and a high voltage supporting body/drift junction is formed in said epitaxial layer.

Claim 24

The MOSFET semiconductor device of claim 8 wherein said doped semiconductor substrate, said doped drift region and said doped epitaxial layer are of one conductivity type, and said device further comprises: at least one body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in said top surface of said epitaxial layer; at least one source region of said one conductivity type formed in a portion of said body region at said top surface and forming a channel region in said top surface between said source region and said epitaxial layer; a gate electrode disposed atop said top surface and overlaying and being insulated from said channel region and being operable to invert said channel region in response to a suitable gate voltage supplied thereto; an overlaying insulation layer formed atop said gate electrode; a source electrode disposed at least atop said source region; and a drain electrode disposed on said bottom surface of said semiconductor substrate.

Claim 25

The semiconductor device of claim 22, wherein a high voltage supporting P body/N - drift junction is formed at the epitaxial layer/higher band-gap material hetero-junction.

Claim 26

The semiconductor device of claim 22, wherein a high voltage supporting P body/N - drift junction is formed in said epitaxial layer.

Claim 27

The semiconductor device of claim 22, wherein a high voltage supporting P body/N - drift junction is formed in said higher band-gap material.

Claim 28

A semiconductor diode comprising: a doped semiconductor substrate which-forms part of the conduction path; a doped drift region comprised of a material having a band gap that is greater than that of said semiconductor substrate and being disposed on the doped semiconductor substrate; a doped epitaxial layer of semiconductor material having a smaller band gap than said drift region and being disposed on the high band-gap material; at least one electrode disposed on a top surface of said epitaxial layer; and at least another electrode disposed on a bottom surface of said semiconductor substrate.

Claim 29

A semiconductor diode comprising: a doped semiconductor substrate which-forms part of the conduction path; a doped drift region comprised of a material having a band gap that is greater than that of said semiconductor substrate and being disposed on the doped semiconductor substrate; a doped epitaxial layer of semiconductor material having a smaller band gap than said drift region and being disposed on the high band-gap material; at least one electrode disposed on a top surface of said epitaxial layer; and at least another electrode disposed on a bottom surface of said semiconductor substrate.

Claim 30

The semiconductor diode of claim 26, wherein the material forming said drift region is a low dielectric constant, high carrier mobility material.

Claim 31

The semiconductor diode of claim 26, wherein the epitaxial layer of semiconductor material is about three μm thick.

Claim 32

The semiconductor diode of claim 26, wherein the semiconductor substrate material is silicon.

Claim 33

The semiconductor diode of claim 26, wherein the material forming said drift region is silicon carbide.

Claim 34

The semiconductor diode of claim 26, wherein the epitaxial layer of semiconductor material is silicon.

Claim 35

The semiconductor diode of claim 26, wherein the semiconductor substrate material is silicon, and the material forming said drift region is silicon carbide.

Claim 36

A semiconductor device comprising: a semiconductor substrate; a high band-gap material forming a drift region disposed on the semiconductor substrate; an epitaxial layer of semiconductor material disposed on the high band-gap material; said doped semiconductor substrate and said doped drift region being of one conductivity type; a trench formed in at least said doped epitaxial layer; a thin insulating layer formed on the walls and bottom surface of said trench; a region of polysilicon formed in said trench such that said trench is filled, thereby forming a gate electrode; a body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in a top surface of said epitaxial layer at least adjoining said trench; a source region of said one conductivity type formed in the top surface of said epitaxial layer in at least a portion of said body region adjoining said trench and forming a channel region in said body region between said source region and said epitaxial layer; a source electrode formed on said top surface of said epitaxial layer; and a drain electrode formed on a bottom surface of said doped semiconductor substrate.

Claim 37

A semiconductor device comprising: a semiconductor substrate; a high band-gap material forming a drift region disposed on the semiconductor substrate; an epitaxial layer of semiconductor material disposed on the high band-gap material; said doped semiconductor substrate and said doped drift region being of one conductivity type; a trench formed in at least said doped epitaxial layer; a thin insulating layer formed on the walls and bottom surface of said trench; a region of polysilicon formed in said trench such that said trench is filled, thereby forming a gate electrode; a body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in a top surface of said epitaxial layer at least adjoining said trench; a source region of said one conductivity type formed in the top surface of said epitaxial layer in at least a portion of said body region adjoining said trench and forming a channel region in said body region between said source region and said epitaxial layer; a source electrode formed on said top surface of said epitaxial layer; and a drain electrode formed on a bottom surface of said doped semiconductor substrate.

Claim 38

The MOSFET semiconductor device of claim 33 wherein said trench is further formed in said higher band-gap material, and a high voltage supporting body/drift junction is formed at the epitaxial layer/high band-gap material hetero-junction.

Claim 39

The MOSFET semiconductor device of claim 33 wherein said trench is further formed in said higher band-gap material, and a high voltage supporting body/drift junction is formed in said high band-gap material.

Claim 40

The MOSFET semiconductor device of claim 33 wherein said doped epitaxial layer is of said one conductivity type, and a high voltage supporting body/drift junction is formed in said epitaxial layer.

Claim 41

The MOSFET semiconductor device of claim 33, wherein the semiconductor substrate material is silicon.

Claim 42

The MOSFET semiconductor device of claim 33, wherein the high band-gap material forming a drift region is silicon carbide.

Claim 43

The MOSFET semiconductor device of claim 33, wherein the epitaxial layer of semiconductor material is silicon.

Claim 44

A semiconductor device comprising: a semiconductor substrate; a high band-gap material forming a drift region disposed on the semiconductor substrate; an epitaxial layer of semiconductor material disposed on the high band-gap material; said doped semiconductor substrate, said doped drift region and said doped epitaxial layer are of one conductivity type; at least one body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in a top surface of said epitaxial layer; at least one source region of said one conductivity type formed in a portion of said body region at said top surface and forming a channel region in said top surface between said source region and said epitaxial layer; a gate electrode disposed atop said top surface and overlaying and being insulated from said channel region and being operable to invert said channel region in response to a suitable gate voltage supplied thereto; an overlaying insulation layer formed atop said gate electrode; a source electrode disposed at least atop said source region; and a drain electrode disposed on a bottom surface of said semiconductor substrate.

Claim 45

A semiconductor device comprising: a semiconductor substrate; a high band-gap material forming a drift region disposed on the semiconductor substrate; an epitaxial layer of semiconductor material disposed on the high band-gap material; said doped semiconductor substrate, said doped drift region and said doped epitaxial layer are of one conductivity type; at least one body region of another conductivity type, which is of opposite conductivity type to said one conductivity type, formed in a top surface of said epitaxial layer; at least one source region of said one conductivity type formed in a portion of said body region at said top surface and forming a channel region in said top surface between said source region and said epitaxial layer; a gate electrode disposed atop said top surface and overlaying and being insulated from said channel region and being operable to invert said channel region in response to a suitable gate voltage supplied thereto; an overlaying insulation layer formed atop said gate electrode; a source electrode disposed at least atop said source region; and a drain electrode disposed on a bottom surface of said semiconductor substrate.

Claim 46

The semiconductor device of claim 40, wherein a high voltage supporting P body/N - drift junction is formed at the epitaxial layer/higher band-gap material hetero-junction.

Claim 47

The semiconductor device of claim 40, wherein a high voltage supporting P body/N - drift junction is formed in said epitaxial layer.

Claim 48

The semiconductor device of claim 40, wherein a high voltage supporting P body/N - drift junction is formed in said higher band-gap material.

Claim 49

The MOSFET semiconductor device of claim 40, wherein the semiconductor substrate material is silicon.

Claim 50

The MOSFET semiconductor device of claim 40, wherein the high band-gap material forming a drift region is silicon carbide.

Claim 51

The MOSFET semiconductor device of claim 40, wherein the epitaxial layer of semiconductor material is silicon.