Patent
US 8,748,244Enhancement and Depletion Mode GaN HEMTs on the Same substrate
Andrea Corrion
US
Copyright © 2026 Matter42. All rights reserved.
Patent
Atlas literature
Patent
US 8,748,244Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Figure 4: Modulation from D- to E-mode using GaN Cap layer (only) regrowth
Figure 5: Modulation from E- to D-mode using GaN Cap layer (only) regrowth 25
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
Figure 7: Calculated boundary between E- and D-mode HEMT operation (lower curve), as well as the onset of relaxation of strained AlGaN on GaN based on the Griffith criterion for Channel crack 5 formation (upper curve) for varying A lxGaix N compositions and thicknesses. The onset of AlGaN relaxation …
Figure 8 Calculated boundary between E and D Mode HEMT operation for three Cap layer thicknesses. 10 [0020] The following papers are incorporated by reference as though fully set forth herein: [1] O. Ambacher, J. Smart, J. R. Shealy, N. G. Weimann, K. Chu, M. Murphy, W. J. Schaff, and L. F. Eastman, …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
The following claims replace all previously submitted claims.
45678910. We CLAIM: Claims 1-10
5161718. Claims 14-18
4. The foregoing notwithstanding, kindly note that the Commissioner is hereby authorized 1 0 to charge any additional fees which may be required or credit overpayment to Deposit Account No. 50-3984. I n particular, if this response is not timely filed, then the Commissioner is hereby authorized to treat this response as including a petition to extend the time period f or response, pursuant to 37 CR. 136(a), said petition requesting an extension of time of the number of months
Layer stacks claimed or described, ordered top of device to substrate.
Enhancement-mode GaN HEMT
Depletion-mode GaN HEMT
Materials described outside the worked examples.
GaN
AlxGa₁-xN
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
minimum separation between E-mode and D-mode regions on same die | 10 nm | — |
Channel layer thickness (GaN) | 20–40 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,748,244Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Figure 4: Modulation from D- to E-mode using GaN Cap layer (only) regrowth
Figure 5: Modulation from E- to D-mode using GaN Cap layer (only) regrowth 25
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
Figure 7: Calculated boundary between E- and D-mode HEMT operation (lower curve), as well as the onset of relaxation of strained AlGaN on GaN based on the Griffith criterion for Channel crack 5 formation (upper curve) for varying A lxGaix N compositions and thicknesses. The onset of AlGaN relaxation …
Figure 8 Calculated boundary between E and D Mode HEMT operation for three Cap layer thicknesses. 10 [0020] The following papers are incorporated by reference as though fully set forth herein: [1] O. Ambacher, J. Smart, J. R. Shealy, N. G. Weimann, K. Chu, M. Murphy, W. J. Schaff, and L. F. Eastman, …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
The following claims replace all previously submitted claims.
45678910. We CLAIM: Claims 1-10
5161718. Claims 14-18
4. The foregoing notwithstanding, kindly note that the Commissioner is hereby authorized 1 0 to charge any additional fees which may be required or credit overpayment to Deposit Account No. 50-3984. I n particular, if this response is not timely filed, then the Commissioner is hereby authorized to treat this response as including a petition to extend the time period f or response, pursuant to 37 CR. 136(a), said petition requesting an extension of time of the number of months
Layer stacks claimed or described, ordered top of device to substrate.
Enhancement-mode GaN HEMT
Depletion-mode GaN HEMT
Materials described outside the worked examples.
GaN
AlxGa₁-xN
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
minimum separation between E-mode and D-mode regions on same die | 10 nm | — |
Channel layer thickness (GaN) | 20–40 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,748,244Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Figure 4: Modulation from D- to E-mode using GaN Cap layer (only) regrowth
Figure 5: Modulation from E- to D-mode using GaN Cap layer (only) regrowth 25
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
Figure 7: Calculated boundary between E- and D-mode HEMT operation (lower curve), as well as the onset of relaxation of strained AlGaN on GaN based on the Griffith criterion for Channel crack 5 formation (upper curve) for varying A lxGaix N compositions and thicknesses. The onset of AlGaN relaxation …
Figure 8 Calculated boundary between E and D Mode HEMT operation for three Cap layer thicknesses. 10 [0020] The following papers are incorporated by reference as though fully set forth herein: [1] O. Ambacher, J. Smart, J. R. Shealy, N. G. Weimann, K. Chu, M. Murphy, W. J. Schaff, and L. F. Eastman, …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
The following claims replace all previously submitted claims.
45678910. We CLAIM: Claims 1-10
5161718. Claims 14-18
4. The foregoing notwithstanding, kindly note that the Commissioner is hereby authorized 1 0 to charge any additional fees which may be required or credit overpayment to Deposit Account No. 50-3984. I n particular, if this response is not timely filed, then the Commissioner is hereby authorized to treat this response as including a petition to extend the time period f or response, pursuant to 37 CR. 136(a), said petition requesting an extension of time of the number of months
Layer stacks claimed or described, ordered top of device to substrate.
Enhancement-mode GaN HEMT
Depletion-mode GaN HEMT
Materials described outside the worked examples.
GaN
AlxGa₁-xN
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
minimum separation between E-mode and D-mode regions on same die | 10 nm | — |
Channel layer thickness (GaN) | 20–40 nm |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,748,244Patent drawings and their descriptions. Click a drawing to enlarge it.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Figure 4: Modulation from D- to E-mode using GaN Cap layer (only) regrowth
Figure 5: Modulation from E- to D-mode using GaN Cap layer (only) regrowth 25
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
Figure 7: Calculated boundary between E- and D-mode HEMT operation (lower curve), as well as the onset of relaxation of strained AlGaN on GaN based on the Griffith criterion for Channel crack 5 formation (upper curve) for varying A lxGaix N compositions and thicknesses. The onset of AlGaN relaxation …
Figure 8 Calculated boundary between E and D Mode HEMT operation for three Cap layer thicknesses. 10 [0020] The following papers are incorporated by reference as though fully set forth herein: [1] O. Ambacher, J. Smart, J. R. Shealy, N. G. Weimann, K. Chu, M. Murphy, W. J. Schaff, and L. F. Eastman, …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
The following claims replace all previously submitted claims.
45678910. We CLAIM: Claims 1-10
5161718. Claims 14-18
4. The foregoing notwithstanding, kindly note that the Commissioner is hereby authorized 1 0 to charge any additional fees which may be required or credit overpayment to Deposit Account No. 50-3984. I n particular, if this response is not timely filed, then the Commissioner is hereby authorized to treat this response as including a petition to extend the time period f or response, pursuant to 37 CR. 136(a), said petition requesting an extension of time of the number of months
Layer stacks claimed or described, ordered top of device to substrate.
Enhancement-mode GaN HEMT
Depletion-mode GaN HEMT
Materials described outside the worked examples.
GaN
AlxGa₁-xN
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
Figure 1: Structure of depletion mode (D-mode) and enhancement mode (E-mode) FETs showing schematically the different thicknesses and compositions achievable with Cap and Ba rri er layer regrowth. Final source, drain and gate structures, insulating coatings, passivation coatings and 15 field plates …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
minimum separation between E-mode and D-mode regions on same die | 10 nm | — |
Channel layer thickness (GaN) | 20–40 nm |
Related documents with shared materials, methods, properties, or citations.
Integrated E-mode and D-mode GaN HEMT on same die
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
GaN |
First Cap layer thickness (E-mode, fifth embodiment) | 2.5 nm | GaN |
First Barrier layer thickness (E-mode, fifth embodiment) | 2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, fifth embodiment) | 2.6 nm | AlxGa(1-x)N |
First Cap layer thickness (E-mode, another embodiment) | 1 nm | GaN |
Second Cap layer thickness (D-mode, another embodiment) | 50 nm | GaN |
First Barrier layer thickness (E-mode, another embodiment) | 1.2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, another embodiment) | 20 nm | AlxGa(1-x)N |
Thickness | 10–20 nm | — |
Thickness | ≥ 0.26 nm | — |
Integrated E-mode and D-mode GaN HEMT on same die
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
GaN |
First Cap layer thickness (E-mode, fifth embodiment) | 2.5 nm | GaN |
First Barrier layer thickness (E-mode, fifth embodiment) | 2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, fifth embodiment) | 2.6 nm | AlxGa(1-x)N |
First Cap layer thickness (E-mode, another embodiment) | 1 nm | GaN |
Second Cap layer thickness (D-mode, another embodiment) | 50 nm | GaN |
First Barrier layer thickness (E-mode, another embodiment) | 1.2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, another embodiment) | 20 nm | AlxGa(1-x)N |
Thickness | 10–20 nm | — |
Thickness | ≥ 0.26 nm | — |
Integrated E-mode and D-mode GaN HEMT on same die
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
GaN |
First Cap layer thickness (E-mode, fifth embodiment) | 2.5 nm | GaN |
First Barrier layer thickness (E-mode, fifth embodiment) | 2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, fifth embodiment) | 2.6 nm | AlxGa(1-x)N |
First Cap layer thickness (E-mode, another embodiment) | 1 nm | GaN |
Second Cap layer thickness (D-mode, another embodiment) | 50 nm | GaN |
First Barrier layer thickness (E-mode, another embodiment) | 1.2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, another embodiment) | 20 nm | AlxGa(1-x)N |
Thickness | 10–20 nm | — |
Thickness | ≥ 0.26 nm | — |
Integrated E-mode and D-mode GaN HEMT on same die
Figure 6: Scanning Electron Micrograph images showing 6a E-mode regions surrounded by D- mode epitaxially-regrown regions, and 6b the E- and D-mode epitaxial layer interface.
GaN |
First Cap layer thickness (E-mode, fifth embodiment) | 2.5 nm | GaN |
First Barrier layer thickness (E-mode, fifth embodiment) | 2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, fifth embodiment) | 2.6 nm | AlxGa(1-x)N |
First Cap layer thickness (E-mode, another embodiment) | 1 nm | GaN |
Second Cap layer thickness (D-mode, another embodiment) | 50 nm | GaN |
First Barrier layer thickness (E-mode, another embodiment) | 1.2 nm | AlxGa(1-x)N |
Second Barrier layer thickness (D-mode, another embodiment) | 20 nm | AlxGa(1-x)N |
Thickness | 10–20 nm | — |
Thickness | ≥ 0.26 nm | — |