Patent
US 8,471,264OF THE INVENTION
Fumitake NAKANISHI
US
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Patent
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Patent
US 8,471,264Patent drawings and their descriptions. Click a drawing to enlarge it.
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 of manufacturing a GaN substrate having a c-plane for manufacturing an epitaxialwafer by successively stacking at least two layers including an AlxGa(,x) N layer having an Al composition x of over zero and not more than 0.3 and a thickness of over zero and not more than 30 nm and a GaN layer on said c-plane, 5 comprising the steps of: deciding a value t 1 found by the following expression 1 as the minimum thickness of said GaN substrate: (1.5 x10" xt13+1.2 x10u xt23) x {1/(1.5 x 10"xt 1)+1/(1.2 x 10"xt2) }/{1 5.96 xxx(1- a2/a l)}x(t1 +t2)+(t 1 xt2)/{5.32 xxx(1- a2/a l)}-(r2+h2)/2h=0 " (expression 1) 10 assuming that t l (m) represents the thickness of said GaN substrate, r (m) represents the radius of said GaN substrate, t2 (m) represents the.thickness of said A lxGa(l-) N layer, x represents the Al composition in said Al xGa(-x)N layer, h (m) represents a warp of said epitaxialwafer, al represents the lattice constant of GaN and a2 represents the lattice constant of Al N; and 15 cutting out said GaN substrate having a thickness of at least said minimum thickness and less than 400 m from an ingot of GaN.
The method of manufacturing a GaN substrate according to claim 1, forming said GaN substrate having a thickness, at least said minimum thickness, of at least 100 m and less than 250 m in said step of cutting out said GaN substrate.
A method of manufacturing an epitaxialwafer, comprising the steps of: manufacturing a G aN substrate by the method of manufacturing a GaN substrate according to claim 1; forming an Al xGaox) N layer on said c-plane of said GaN substrate; and 5 forming a GaN layer on said Al xGa(,x) N layer.
An epitaxialwafer comprising a GaN substrate, an A lxGaapx) N layer formed on a c-plane of said GaN substrate and a GaN layer formed on said A lXGa.X) N layer, wherein the thickness of said GaN substrate is less than 250 m, and 5 a warp of said epitaxialwafer is not more than 100 m.
Layer stacks claimed or described, ordered top of device to substrate.
epitaxialwafer
Materials described outside the worked examples.
GaN substrate
GaN
AlxGa(1-x)N layer
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
epitaxialwafer warp (claimed upper bound) | 100 um | — |
GaN substrate thickness (claimed upper bound, claim 5) |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,471,264Patent drawings and their descriptions. Click a drawing to enlarge it.
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 of manufacturing a GaN substrate having a c-plane for manufacturing an epitaxialwafer by successively stacking at least two layers including an AlxGa(,x) N layer having an Al composition x of over zero and not more than 0.3 and a thickness of over zero and not more than 30 nm and a GaN layer on said c-plane, 5 comprising the steps of: deciding a value t 1 found by the following expression 1 as the minimum thickness of said GaN substrate: (1.5 x10" xt13+1.2 x10u xt23) x {1/(1.5 x 10"xt 1)+1/(1.2 x 10"xt2) }/{1 5.96 xxx(1- a2/a l)}x(t1 +t2)+(t 1 xt2)/{5.32 xxx(1- a2/a l)}-(r2+h2)/2h=0 " (expression 1) 10 assuming that t l (m) represents the thickness of said GaN substrate, r (m) represents the radius of said GaN substrate, t2 (m) represents the.thickness of said A lxGa(l-) N layer, x represents the Al composition in said Al xGa(-x)N layer, h (m) represents a warp of said epitaxialwafer, al represents the lattice constant of GaN and a2 represents the lattice constant of Al N; and 15 cutting out said GaN substrate having a thickness of at least said minimum thickness and less than 400 m from an ingot of GaN.
The method of manufacturing a GaN substrate according to claim 1, forming said GaN substrate having a thickness, at least said minimum thickness, of at least 100 m and less than 250 m in said step of cutting out said GaN substrate.
A method of manufacturing an epitaxialwafer, comprising the steps of: manufacturing a G aN substrate by the method of manufacturing a GaN substrate according to claim 1; forming an Al xGaox) N layer on said c-plane of said GaN substrate; and 5 forming a GaN layer on said Al xGa(,x) N layer.
An epitaxialwafer comprising a GaN substrate, an A lxGaapx) N layer formed on a c-plane of said GaN substrate and a GaN layer formed on said A lXGa.X) N layer, wherein the thickness of said GaN substrate is less than 250 m, and 5 a warp of said epitaxialwafer is not more than 100 m.
Layer stacks claimed or described, ordered top of device to substrate.
epitaxialwafer
Materials described outside the worked examples.
GaN substrate
GaN
AlxGa(1-x)N layer
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
epitaxialwafer warp (claimed upper bound) | 100 um | — |
GaN substrate thickness (claimed upper bound, claim 5) |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,471,264Patent drawings and their descriptions. Click a drawing to enlarge it.
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 of manufacturing a GaN substrate having a c-plane for manufacturing an epitaxialwafer by successively stacking at least two layers including an AlxGa(,x) N layer having an Al composition x of over zero and not more than 0.3 and a thickness of over zero and not more than 30 nm and a GaN layer on said c-plane, 5 comprising the steps of: deciding a value t 1 found by the following expression 1 as the minimum thickness of said GaN substrate: (1.5 x10" xt13+1.2 x10u xt23) x {1/(1.5 x 10"xt 1)+1/(1.2 x 10"xt2) }/{1 5.96 xxx(1- a2/a l)}x(t1 +t2)+(t 1 xt2)/{5.32 xxx(1- a2/a l)}-(r2+h2)/2h=0 " (expression 1) 10 assuming that t l (m) represents the thickness of said GaN substrate, r (m) represents the radius of said GaN substrate, t2 (m) represents the.thickness of said A lxGa(l-) N layer, x represents the Al composition in said Al xGa(-x)N layer, h (m) represents a warp of said epitaxialwafer, al represents the lattice constant of GaN and a2 represents the lattice constant of Al N; and 15 cutting out said GaN substrate having a thickness of at least said minimum thickness and less than 400 m from an ingot of GaN.
The method of manufacturing a GaN substrate according to claim 1, forming said GaN substrate having a thickness, at least said minimum thickness, of at least 100 m and less than 250 m in said step of cutting out said GaN substrate.
A method of manufacturing an epitaxialwafer, comprising the steps of: manufacturing a G aN substrate by the method of manufacturing a GaN substrate according to claim 1; forming an Al xGaox) N layer on said c-plane of said GaN substrate; and 5 forming a GaN layer on said Al xGa(,x) N layer.
An epitaxialwafer comprising a GaN substrate, an A lxGaapx) N layer formed on a c-plane of said GaN substrate and a GaN layer formed on said A lXGa.X) N layer, wherein the thickness of said GaN substrate is less than 250 m, and 5 a warp of said epitaxialwafer is not more than 100 m.
Layer stacks claimed or described, ordered top of device to substrate.
epitaxialwafer
Materials described outside the worked examples.
GaN substrate
GaN
AlxGa(1-x)N layer
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
epitaxialwafer warp (claimed upper bound) | 100 um | — |
GaN substrate thickness (claimed upper bound, claim 5) |
Related documents with shared materials, methods, properties, or citations.
Patent
Atlas literature
Patent
US 8,471,264Patent drawings and their descriptions. Click a drawing to enlarge it.
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 of manufacturing a GaN substrate having a c-plane for manufacturing an epitaxialwafer by successively stacking at least two layers including an AlxGa(,x) N layer having an Al composition x of over zero and not more than 0.3 and a thickness of over zero and not more than 30 nm and a GaN layer on said c-plane, 5 comprising the steps of: deciding a value t 1 found by the following expression 1 as the minimum thickness of said GaN substrate: (1.5 x10" xt13+1.2 x10u xt23) x {1/(1.5 x 10"xt 1)+1/(1.2 x 10"xt2) }/{1 5.96 xxx(1- a2/a l)}x(t1 +t2)+(t 1 xt2)/{5.32 xxx(1- a2/a l)}-(r2+h2)/2h=0 " (expression 1) 10 assuming that t l (m) represents the thickness of said GaN substrate, r (m) represents the radius of said GaN substrate, t2 (m) represents the.thickness of said A lxGa(l-) N layer, x represents the Al composition in said Al xGa(-x)N layer, h (m) represents a warp of said epitaxialwafer, al represents the lattice constant of GaN and a2 represents the lattice constant of Al N; and 15 cutting out said GaN substrate having a thickness of at least said minimum thickness and less than 400 m from an ingot of GaN.
The method of manufacturing a GaN substrate according to claim 1, forming said GaN substrate having a thickness, at least said minimum thickness, of at least 100 m and less than 250 m in said step of cutting out said GaN substrate.
A method of manufacturing an epitaxialwafer, comprising the steps of: manufacturing a G aN substrate by the method of manufacturing a GaN substrate according to claim 1; forming an Al xGaox) N layer on said c-plane of said GaN substrate; and 5 forming a GaN layer on said Al xGa(,x) N layer.
An epitaxialwafer comprising a GaN substrate, an A lxGaapx) N layer formed on a c-plane of said GaN substrate and a GaN layer formed on said A lXGa.X) N layer, wherein the thickness of said GaN substrate is less than 250 m, and 5 a warp of said epitaxialwafer is not more than 100 m.
Layer stacks claimed or described, ordered top of device to substrate.
epitaxialwafer
Materials described outside the worked examples.
GaN substrate
GaN
AlxGa(1-x)N layer
AlxGa(1-x)N
Additional fabrication and treatment steps described in the patent.
Performance values and ranges asserted in the specification or claims.
| Property | Value | Material |
|---|---|---|
epitaxialwafer warp (claimed upper bound) | 100 um | — |
GaN substrate thickness (claimed upper bound, claim 5) |
Related documents with shared materials, methods, properties, or citations.
GaN |
GaN substrate thickness (claimed range, claim 1) | — | GaN |
GaN substrate thickness (claimed preferred range, claim 2) | — | GaN |
Thickness | ≥ 30 nm | — |
Thickness | ≥ 20 nm | — |
Thickness | ≥ 25 nm | — |
Thickness | ≥ 3 nm | — |
GaN |
GaN substrate thickness (claimed range, claim 1) | — | GaN |
GaN substrate thickness (claimed preferred range, claim 2) | — | GaN |
Thickness | ≥ 30 nm | — |
Thickness | ≥ 20 nm | — |
Thickness | ≥ 25 nm | — |
Thickness | ≥ 3 nm | — |
GaN |
GaN substrate thickness (claimed range, claim 1) | — | GaN |
GaN substrate thickness (claimed preferred range, claim 2) | — | GaN |
Thickness | ≥ 30 nm | — |
Thickness | ≥ 20 nm | — |
Thickness | ≥ 25 nm | — |
Thickness | ≥ 3 nm | — |
GaN |
GaN substrate thickness (claimed range, claim 1) | — | GaN |
GaN substrate thickness (claimed preferred range, claim 2) | — | GaN |
Thickness | ≥ 30 nm | — |
Thickness | ≥ 20 nm | — |
Thickness | ≥ 25 nm | — |
Thickness | ≥ 3 nm | — |