Patent
US 8,772,786GALLIUM NITRIDE DEVICES HAVING LOW OHMIC CONTACT RESISTANCE
Kamal Tabatabaie, William E. Hoke, Eduardo M. Chumbes, Kevin McCarthy
US
Copyright © 2026 Matter42. All rights reserved.
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Atlas literature
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US 8,772,786Patent drawings and their descriptions. Click a drawing to enlarge it.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
Cancel claims 1-4.
The sendutor strte recited ilaim ^ A semiconductor structure, comprising: a substrate; a mesa structure disposed on a surface of the substrate, the mesa structure having slopped sidewalls obli q ue to the surface of the substrate, comprising: an electron donor layer disposed on, and along, the sloped sidewall of the mesa structure; a lower semiconductor layer having ends of an upper portion terminating at a lower portion of the electron donor layer; an upper semiconductor layer having ends terminating at an upper portion of the electron donor layer, having a different band g ap from, and in direct contact with, the lower semiconductor layer; wherein a two-dimension electron g as re g ion is formed having one portion disposed along a bottom portion of the upper semiconductor layer and another portion disposed alon g lower portions of the electron donor layer; an ohmic contact material disposed on the electron donor layer; wherein the upper semiconductor la y er includes A lN; wherein the lower semiconductor layer is GaN; and wherein the electron donor layer is n-type doped AlGaN.
The semiconductor structure recited in claim 5 wherein the ohmic contact material is n-type doped GaN.
Cancel claims 9- 13. including a gate electrode in Schottky contact including an ohmic contact in contact with the
Layer stacks claimed or described, ordered top of device to substrate.
GaN HEMT with sidewall ohmic contact (sideway HEMT)
GaN HEMT with sidewall AlGaN electron donor and N+ GaN ohmic contact (description embodiment)
Materials described outside the worked examples.
GaN
AlN
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
ohmic contact resistance target (second generation GaN HEMT) | — | — |
ohmic contact resistance prior art Ti/Al/Barrier/Au annealed contacts | — | — |
Thickness |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,772,786Patent drawings and their descriptions. Click a drawing to enlarge it.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
Cancel claims 1-4.
The sendutor strte recited ilaim ^ A semiconductor structure, comprising: a substrate; a mesa structure disposed on a surface of the substrate, the mesa structure having slopped sidewalls obli q ue to the surface of the substrate, comprising: an electron donor layer disposed on, and along, the sloped sidewall of the mesa structure; a lower semiconductor layer having ends of an upper portion terminating at a lower portion of the electron donor layer; an upper semiconductor layer having ends terminating at an upper portion of the electron donor layer, having a different band g ap from, and in direct contact with, the lower semiconductor layer; wherein a two-dimension electron g as re g ion is formed having one portion disposed along a bottom portion of the upper semiconductor layer and another portion disposed alon g lower portions of the electron donor layer; an ohmic contact material disposed on the electron donor layer; wherein the upper semiconductor la y er includes A lN; wherein the lower semiconductor layer is GaN; and wherein the electron donor layer is n-type doped AlGaN.
The semiconductor structure recited in claim 5 wherein the ohmic contact material is n-type doped GaN.
Cancel claims 9- 13. including a gate electrode in Schottky contact including an ohmic contact in contact with the
Layer stacks claimed or described, ordered top of device to substrate.
GaN HEMT with sidewall ohmic contact (sideway HEMT)
GaN HEMT with sidewall AlGaN electron donor and N+ GaN ohmic contact (description embodiment)
Materials described outside the worked examples.
GaN
AlN
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
ohmic contact resistance target (second generation GaN HEMT) | — | — |
ohmic contact resistance prior art Ti/Al/Barrier/Au annealed contacts | — | — |
Thickness |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,772,786Patent drawings and their descriptions. Click a drawing to enlarge it.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
Cancel claims 1-4.
The sendutor strte recited ilaim ^ A semiconductor structure, comprising: a substrate; a mesa structure disposed on a surface of the substrate, the mesa structure having slopped sidewalls obli q ue to the surface of the substrate, comprising: an electron donor layer disposed on, and along, the sloped sidewall of the mesa structure; a lower semiconductor layer having ends of an upper portion terminating at a lower portion of the electron donor layer; an upper semiconductor layer having ends terminating at an upper portion of the electron donor layer, having a different band g ap from, and in direct contact with, the lower semiconductor layer; wherein a two-dimension electron g as re g ion is formed having one portion disposed along a bottom portion of the upper semiconductor layer and another portion disposed alon g lower portions of the electron donor layer; an ohmic contact material disposed on the electron donor layer; wherein the upper semiconductor la y er includes A lN; wherein the lower semiconductor layer is GaN; and wherein the electron donor layer is n-type doped AlGaN.
The semiconductor structure recited in claim 5 wherein the ohmic contact material is n-type doped GaN.
Cancel claims 9- 13. including a gate electrode in Schottky contact including an ohmic contact in contact with the
Layer stacks claimed or described, ordered top of device to substrate.
GaN HEMT with sidewall ohmic contact (sideway HEMT)
GaN HEMT with sidewall AlGaN electron donor and N+ GaN ohmic contact (description embodiment)
Materials described outside the worked examples.
GaN
AlN
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
ohmic contact resistance target (second generation GaN HEMT) | — | — |
ohmic contact resistance prior art Ti/Al/Barrier/Au annealed contacts | — | — |
Thickness |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,772,786Patent drawings and their descriptions. Click a drawing to enlarge it.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
Cancel claims 1-4.
The sendutor strte recited ilaim ^ A semiconductor structure, comprising: a substrate; a mesa structure disposed on a surface of the substrate, the mesa structure having slopped sidewalls obli q ue to the surface of the substrate, comprising: an electron donor layer disposed on, and along, the sloped sidewall of the mesa structure; a lower semiconductor layer having ends of an upper portion terminating at a lower portion of the electron donor layer; an upper semiconductor layer having ends terminating at an upper portion of the electron donor layer, having a different band g ap from, and in direct contact with, the lower semiconductor layer; wherein a two-dimension electron g as re g ion is formed having one portion disposed along a bottom portion of the upper semiconductor layer and another portion disposed alon g lower portions of the electron donor layer; an ohmic contact material disposed on the electron donor layer; wherein the upper semiconductor la y er includes A lN; wherein the lower semiconductor layer is GaN; and wherein the electron donor layer is n-type doped AlGaN.
The semiconductor structure recited in claim 5 wherein the ohmic contact material is n-type doped GaN.
Cancel claims 9- 13. including a gate electrode in Schottky contact including an ohmic contact in contact with the
Layer stacks claimed or described, ordered top of device to substrate.
GaN HEMT with sidewall ohmic contact (sideway HEMT)
GaN HEMT with sidewall AlGaN electron donor and N+ GaN ohmic contact (description embodiment)
Materials described outside the worked examples.
GaN
AlN
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIGS. 1A- 1 C. Here, a substrate of, for example, silicon carbide (SiC) or silicon Si, has a gallium nitride (GaN) layer epitaxial formed on the substrate. A …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
ohmic contact resistance target (second generation GaN HEMT) | — | — |
ohmic contact resistance prior art Ti/Al/Barrier/Au annealed contacts | — | — |
Thickness |
Related documents with shared materials, methods, properties, or citations.
n-type doped AlGaN
AlGaN
InAlN
InGaAlN
SiC substrate
SiC
Si substrate
Si
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
| 300–1000 Å |
| — |
Thickness | 30–200 Å | — |
Thickness | 50–100 Å | — |
Thickness | 200–1000 Å | — |
n-type doped AlGaN
AlGaN
InAlN
InGaAlN
SiC substrate
SiC
Si substrate
Si
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
| 300–1000 Å |
| — |
Thickness | 30–200 Å | — |
Thickness | 50–100 Å | — |
Thickness | 200–1000 Å | — |
n-type doped AlGaN
AlGaN
InAlN
InGaAlN
SiC substrate
SiC
Si substrate
Si
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
| 300–1000 Å |
| — |
Thickness | 30–200 Å | — |
Thickness | 50–100 Å | — |
Thickness | 200–1000 Å | — |
n-type doped AlGaN
AlGaN
InAlN
InGaAlN
SiC substrate
SiC
Si substrate
Si
FIG. 2B. Here, the structure 10 shown in FIG, 2A is etched to a depth 25 from 300 Angstrom to 1000 Angstrom (preferably 600 Angstrom). [0017] Next, as shown in
| 300–1000 Å |
| — |
Thickness | 30–200 Å | — |
Thickness | 50–100 Å | — |
Thickness | 200–1000 Å | — |