Patent
Atlas literature
Patent
US 11,817,318 B2Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a plot illustrating aspects of vapor pressure of nitrogen over GaN under a range of temperatures.
FIGS. 2A-2H provide a flow diagram illustrating exem- plary process steps in a method for forming ion-implanted GaN ohmic contacts and for fabricating …
FIGS. 3A and 3B are photographic images illustrating 45 damage caused by thermal annealing GaN above the thermal decomposition limit when a protective cap is …
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method for selectively forming at least one n-doped region in an epitaxial GaN material layer, the method including the steps of: selectively applying a mask to a predetermined region of the GaN material layer; implanting n-type dopant ions into at least one predeter-mined unmasked region of the GaN material layer to form an n-implanted GaN material layer; removing the mask from the n-implanted GaN material layer; subjecting the n-implanted GaN material layer to a first annealing at a predetermined temperature at which the GaN is stable for a predetermined time of a few seconds to several hours; and subsequently subjecting the n-implanted GaN material layer to a second annealing at a predetermined tem-perature between 900 and 1600° C. for a predetermined time between a few seconds and a few hours and at a predetermined pressure between about 1 atm and about 100 bar to activate the implanted n-dopant ions and to produce at least one electrically activated n-doped region within the GaN; wherein the electrically activated n-doped region is planar to an upper surface of the epitaxial GaN material layer and has a concentration of activated implanted n-type dopant ions of about 1018 cm⁻³ to about 1022 cm⁻³.
The method according to claim 1, wherein the first annealing is conducted at a temperature of about 850° C. for several hours at atmospheric pressure.
The method according to claim 1, wherein the first annealing is conducted at a temperature between about 850° C. and about 1050° C. for a few minutes at atmospheric pressure.
The method according to claim 1, further including applying a thermally protective cap to an upper surface of the n-implanted GaN before annealing, the cap being con-figured to suppress evolution of nitrogen from the GaN during annealing.
The method according to claim 1, further including applying a nitrogen overpressure of up to about 100 bar during the second annealing to further stabilize the GaN. 9
The method according to claim 1, wherein the second annealing is conducted by means of laser annealing or rapid thermal annealing (RTA).
The method according to claim 1, wherein the n-dopant ions comprise Si or Ge.
The method according to claim 1, wherein the GaN material layer comprises unintentionally doped GaN, semiinsulating GaN, carbon-doped GaN, or an AlGaN/GaN heterostructure.
The method according to claim 1, wherein the GaN material layer is situated on a substrate comprising GaN, SiC, Si, sapphire, or an engineered composite. ∗ ∗ ∗ ∗ ∗
Layer stacks claimed or described, ordered top of device to substrate.
ion-implanted n-doped GaN contact region
GaN HEMT device with ion-implanted ohmic contacts
No layer stack recorded.
AlGaN/GaN heterostructure with ion-implanted contact regions
Materials described outside the worked examples.
epitaxial GaN
GaN
n-type dopant ions
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
activated implanted n-type dopant ion concentration | 1000000000000000000–1e+22 cm⁻³ | GaN |
GaN equilibrium thermal decomposition limit at atmospheric pressure | 850 °C |
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 4
Cited non-patent literature · 3
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 11,817,318 B2Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a plot illustrating aspects of vapor pressure of nitrogen over GaN under a range of temperatures.
FIGS. 2A-2H provide a flow diagram illustrating exem- plary process steps in a method for forming ion-implanted GaN ohmic contacts and for fabricating …
FIGS. 3A and 3B are photographic images illustrating 45 damage caused by thermal annealing GaN above the thermal decomposition limit when a protective cap is …
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method for selectively forming at least one n-doped region in an epitaxial GaN material layer, the method including the steps of: selectively applying a mask to a predetermined region of the GaN material layer; implanting n-type dopant ions into at least one predeter-mined unmasked region of the GaN material layer to form an n-implanted GaN material layer; removing the mask from the n-implanted GaN material layer; subjecting the n-implanted GaN material layer to a first annealing at a predetermined temperature at which the GaN is stable for a predetermined time of a few seconds to several hours; and subsequently subjecting the n-implanted GaN material layer to a second annealing at a predetermined tem-perature between 900 and 1600° C. for a predetermined time between a few seconds and a few hours and at a predetermined pressure between about 1 atm and about 100 bar to activate the implanted n-dopant ions and to produce at least one electrically activated n-doped region within the GaN; wherein the electrically activated n-doped region is planar to an upper surface of the epitaxial GaN material layer and has a concentration of activated implanted n-type dopant ions of about 1018 cm⁻³ to about 1022 cm⁻³.
The method according to claim 1, wherein the first annealing is conducted at a temperature of about 850° C. for several hours at atmospheric pressure.
The method according to claim 1, wherein the first annealing is conducted at a temperature between about 850° C. and about 1050° C. for a few minutes at atmospheric pressure.
The method according to claim 1, further including applying a thermally protective cap to an upper surface of the n-implanted GaN before annealing, the cap being con-figured to suppress evolution of nitrogen from the GaN during annealing.
The method according to claim 1, further including applying a nitrogen overpressure of up to about 100 bar during the second annealing to further stabilize the GaN. 9
The method according to claim 1, wherein the second annealing is conducted by means of laser annealing or rapid thermal annealing (RTA).
The method according to claim 1, wherein the n-dopant ions comprise Si or Ge.
The method according to claim 1, wherein the GaN material layer comprises unintentionally doped GaN, semiinsulating GaN, carbon-doped GaN, or an AlGaN/GaN heterostructure.
The method according to claim 1, wherein the GaN material layer is situated on a substrate comprising GaN, SiC, Si, sapphire, or an engineered composite. ∗ ∗ ∗ ∗ ∗
Layer stacks claimed or described, ordered top of device to substrate.
ion-implanted n-doped GaN contact region
GaN HEMT device with ion-implanted ohmic contacts
No layer stack recorded.
AlGaN/GaN heterostructure with ion-implanted contact regions
Materials described outside the worked examples.
epitaxial GaN
GaN
n-type dopant ions
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
activated implanted n-type dopant ion concentration | 1000000000000000000–1e+22 cm⁻³ | GaN |
GaN equilibrium thermal decomposition limit at atmospheric pressure | 850 °C |
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 4
Cited non-patent literature · 3
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 11,817,318 B2Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a plot illustrating aspects of vapor pressure of nitrogen over GaN under a range of temperatures.
FIGS. 2A-2H provide a flow diagram illustrating exem- plary process steps in a method for forming ion-implanted GaN ohmic contacts and for fabricating …
FIGS. 3A and 3B are photographic images illustrating 45 damage caused by thermal annealing GaN above the thermal decomposition limit when a protective cap is …
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method for selectively forming at least one n-doped region in an epitaxial GaN material layer, the method including the steps of: selectively applying a mask to a predetermined region of the GaN material layer; implanting n-type dopant ions into at least one predeter-mined unmasked region of the GaN material layer to form an n-implanted GaN material layer; removing the mask from the n-implanted GaN material layer; subjecting the n-implanted GaN material layer to a first annealing at a predetermined temperature at which the GaN is stable for a predetermined time of a few seconds to several hours; and subsequently subjecting the n-implanted GaN material layer to a second annealing at a predetermined tem-perature between 900 and 1600° C. for a predetermined time between a few seconds and a few hours and at a predetermined pressure between about 1 atm and about 100 bar to activate the implanted n-dopant ions and to produce at least one electrically activated n-doped region within the GaN; wherein the electrically activated n-doped region is planar to an upper surface of the epitaxial GaN material layer and has a concentration of activated implanted n-type dopant ions of about 1018 cm⁻³ to about 1022 cm⁻³.
The method according to claim 1, wherein the first annealing is conducted at a temperature of about 850° C. for several hours at atmospheric pressure.
The method according to claim 1, wherein the first annealing is conducted at a temperature between about 850° C. and about 1050° C. for a few minutes at atmospheric pressure.
The method according to claim 1, further including applying a thermally protective cap to an upper surface of the n-implanted GaN before annealing, the cap being con-figured to suppress evolution of nitrogen from the GaN during annealing.
The method according to claim 1, further including applying a nitrogen overpressure of up to about 100 bar during the second annealing to further stabilize the GaN. 9
The method according to claim 1, wherein the second annealing is conducted by means of laser annealing or rapid thermal annealing (RTA).
The method according to claim 1, wherein the n-dopant ions comprise Si or Ge.
The method according to claim 1, wherein the GaN material layer comprises unintentionally doped GaN, semiinsulating GaN, carbon-doped GaN, or an AlGaN/GaN heterostructure.
The method according to claim 1, wherein the GaN material layer is situated on a substrate comprising GaN, SiC, Si, sapphire, or an engineered composite. ∗ ∗ ∗ ∗ ∗
Layer stacks claimed or described, ordered top of device to substrate.
ion-implanted n-doped GaN contact region
GaN HEMT device with ion-implanted ohmic contacts
No layer stack recorded.
AlGaN/GaN heterostructure with ion-implanted contact regions
Materials described outside the worked examples.
epitaxial GaN
GaN
n-type dopant ions
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
activated implanted n-type dopant ion concentration | 1000000000000000000–1e+22 cm⁻³ | GaN |
GaN equilibrium thermal decomposition limit at atmospheric pressure | 850 °C |
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 4
Cited non-patent literature · 3
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 11,817,318 B2Patent drawings and their descriptions. Click a drawing to enlarge it.
FIG. 1 is a plot illustrating aspects of vapor pressure of nitrogen over GaN under a range of temperatures.
FIGS. 2A-2H provide a flow diagram illustrating exem- plary process steps in a method for forming ion-implanted GaN ohmic contacts and for fabricating …
FIGS. 3A and 3B are photographic images illustrating 45 damage caused by thermal annealing GaN above the thermal decomposition limit when a protective cap is …
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
Claims define the patent's legal scope. Independent claims stand alone; dependent claims (nested) narrow them. Click a claim to expand its dependents.
A method for selectively forming at least one n-doped region in an epitaxial GaN material layer, the method including the steps of: selectively applying a mask to a predetermined region of the GaN material layer; implanting n-type dopant ions into at least one predeter-mined unmasked region of the GaN material layer to form an n-implanted GaN material layer; removing the mask from the n-implanted GaN material layer; subjecting the n-implanted GaN material layer to a first annealing at a predetermined temperature at which the GaN is stable for a predetermined time of a few seconds to several hours; and subsequently subjecting the n-implanted GaN material layer to a second annealing at a predetermined tem-perature between 900 and 1600° C. for a predetermined time between a few seconds and a few hours and at a predetermined pressure between about 1 atm and about 100 bar to activate the implanted n-dopant ions and to produce at least one electrically activated n-doped region within the GaN; wherein the electrically activated n-doped region is planar to an upper surface of the epitaxial GaN material layer and has a concentration of activated implanted n-type dopant ions of about 1018 cm⁻³ to about 1022 cm⁻³.
The method according to claim 1, wherein the first annealing is conducted at a temperature of about 850° C. for several hours at atmospheric pressure.
The method according to claim 1, wherein the first annealing is conducted at a temperature between about 850° C. and about 1050° C. for a few minutes at atmospheric pressure.
The method according to claim 1, further including applying a thermally protective cap to an upper surface of the n-implanted GaN before annealing, the cap being con-figured to suppress evolution of nitrogen from the GaN during annealing.
The method according to claim 1, further including applying a nitrogen overpressure of up to about 100 bar during the second annealing to further stabilize the GaN. 9
The method according to claim 1, wherein the second annealing is conducted by means of laser annealing or rapid thermal annealing (RTA).
The method according to claim 1, wherein the n-dopant ions comprise Si or Ge.
The method according to claim 1, wherein the GaN material layer comprises unintentionally doped GaN, semiinsulating GaN, carbon-doped GaN, or an AlGaN/GaN heterostructure.
The method according to claim 1, wherein the GaN material layer is situated on a substrate comprising GaN, SiC, Si, sapphire, or an engineered composite. ∗ ∗ ∗ ∗ ∗
Layer stacks claimed or described, ordered top of device to substrate.
ion-implanted n-doped GaN contact region
GaN HEMT device with ion-implanted ohmic contacts
No layer stack recorded.
AlGaN/GaN heterostructure with ion-implanted contact regions
Materials described outside the worked examples.
epitaxial GaN
GaN
n-type dopant ions
Additional fabrication and treatment steps described in the patent.
Measurements and analyses referenced in the patent, with their drawing references.
FIG. 4 is a plot illustrating spectral broadening observed 50 of the Raman A₁(LO) peak indicating damage to a GaN sample incurred due to ion implantation and …
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
activated implanted n-type dopant ion concentration | 1000000000000000000–1e+22 cm⁻³ | GaN |
GaN equilibrium thermal decomposition limit at atmospheric pressure | 850 °C |
Patents and literature cited by this patent (applicant and examiner references).
Cited patents · 4
Cited non-patent literature · 3
Related documents with shared materials, methods, properties, or citations.
Si dopant
Si
Ge dopant
Ge
carbon-doped GaN
GaN:C
AlGaN/GaN heterostructure
AlGaN/GaN
Mg dopant
Mg
Be dopant
Be
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
GaN |
Pressure | 760–75006.2 Torr | — |
Thickness | 3–1022 cm | — |
Temperature | 900–1600 °C | — |
Temperature | 1200–1600 °C | — |
Temperature | ≤ 850 °C | — |
Temperature | 850–1050 °C | — |
Si dopant
Si
Ge dopant
Ge
carbon-doped GaN
GaN:C
AlGaN/GaN heterostructure
AlGaN/GaN
Mg dopant
Mg
Be dopant
Be
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
GaN |
Pressure | 760–75006.2 Torr | — |
Thickness | 3–1022 cm | — |
Temperature | 900–1600 °C | — |
Temperature | 1200–1600 °C | — |
Temperature | ≤ 850 °C | — |
Temperature | 850–1050 °C | — |
Si dopant
Si
Ge dopant
Ge
carbon-doped GaN
GaN:C
AlGaN/GaN heterostructure
AlGaN/GaN
Mg dopant
Mg
Be dopant
Be
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
GaN |
Pressure | 760–75006.2 Torr | — |
Thickness | 3–1022 cm | — |
Temperature | 900–1600 °C | — |
Temperature | 1200–1600 °C | — |
Temperature | ≤ 850 °C | — |
Temperature | 850–1050 °C | — |
Si dopant
Si
Ge dopant
Ge
carbon-doped GaN
GaN:C
AlGaN/GaN heterostructure
AlGaN/GaN
Mg dopant
Mg
Be dopant
Be
FIGS. 5A-5C are plots illustrating electrical properties of unannealed ion-implanted GaN samples and ion-implanted 55 GaN sample that have been annealed in …
GaN |
Pressure | 760–75006.2 Torr | — |
Thickness | 3–1022 cm | — |
Temperature | 900–1600 °C | — |
Temperature | 1200–1600 °C | — |
Temperature | ≤ 850 °C | — |
Temperature | 850–1050 °C | — |
