US5767020A
Expired / Lapsed
US
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Etching solution for etching porous silicon, etching method using the etching solution and method of preparing semiconductor member using the etching solution
Assignee: Canon Inc
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Filing: 1992-02-14
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Granted: 1998-06-16
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Expires: 2012-02-14
Abstract
Abstract A method for preparing a semiconductor member comprises: forming a substrate having a non-porous silicon monocrystalline layer and a porous silicon layer; bonding another substrate having a surface made of an insulating material to the surface of the monocrystalline layer; and etching to remove the porous silicon layer by immersing in an etching solution.
Inventors
- 👤 Kiyofumi Sakaguchi
- 👤 Takao Yonehara
- 👤 Nobuhiko Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 05:03
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1922; H10P50/00; H10P50/60; H10P50/64; H10P50/642; H10P90/12; H10P90/15; H10P90/1914; H10W; H10W10/00; H10W10/10; H10W10/181
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
49 words
An etching method comprising the steps of: providing a substrate having a porous silicon layer and a non-porous silicon layer; and selectively etching the porous silicon layer from the substrate with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 2
Dependent Claim
49 words
An etching method comprising the steps of: providing a substrate having a porous silicon layer and a non-porous silicon layer; and selectively etching the porous silicon layer from the substrate with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 3
Dependent Claim
28 words
The etching method according to claim 1, wherein the etching liquid comprises a solution comprising 1 to 95% of hydrofluoric acid and 1 to 95% of hydrogen peroxide.
Claim 4
Dependent Claim
26 words
The etching method according to claim 1, wherein the etching of the porous silicon layer is carried out at a temperature of 0° to 100° C.
Claim 5
Dependent Claim
26 words
The etching method according to claim 3, wherein the etching of the porous silicon layer is carried out at a temperature of 5° to 80° C.
Claim 6
Dependent Claim
26 words
The etching method according to claim 4, wherein the etching of the porous silicon layer is carried out at a temperature of 5° to 60° C.
Claim 7
Independent Claim
86 words
A method for preparing a semiconductor member which comprises the steps of: providing a first substrate having a porous monocrystalline silicon layer and a non-porous monocrystalline silicon layer; bonding the first substrate to a second substrate with an insulating layer therebetween to place the non-porous monocrystalline silicon layer inside the multi-layer structure obtained; and selectively etching and removing the porous monocrystalline silicon layer from the multi-layer structure with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 8
Independent Claim
86 words
A method for preparing a semiconductor member which comprises the steps of: providing a first substrate having a porous monocrystalline silicon layer and a non-porous monocrystalline silicon layer; bonding the first substrate to a second substrate with an insulating layer therebetween to place the non-porous monocrystalline silicon layer inside the multi-layer structure obtained; and selectively etching and removing the porous monocrystalline silicon layer from the multi-layer structure with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 9
Independent Claim
83 words
A method for preparing a semiconductor member which comprises the steps of: providing a first substrate having a porous monocrystalline silicon layer and a non-porous monocrystalline silicon layer; bonding the first substrate to a second light transmissive substrate to space the non-porous monocrystalline silicon layer inside the multi-layer structure obtained; and selectively etching and removing the porous monocrystalline silicon layer from the multi-layer structure with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 10
Independent Claim
83 words
A method for preparing a semiconductor member which comprises the steps of: providing a first substrate having a porous monocrystalline silicon layer and a non-porous monocrystalline silicon layer; bonding the first substrate to a second light transmissive substrate to space the non-porous monocrystalline silicon layer inside the multi-layer structure obtained; and selectively etching and removing the porous monocrystalline silicon layer from the multi-layer structure with an etching liquid comprising a solution comprising hydrofluoric acid and hydrogen peroxide to leave the non-porous silicon layer.
Claim 11
Dependent Claim
29 words
The method according to claim 6 or 7, wherein the etching liquid comprises a solution comprising 1 to 95% of hydrofluoric acid and 1 to 95% of hydrogen peroxide.
Claim 12
Dependent Claim
28 words
The method according to claim 6 or 7, wherein the etching of the porous monocrystalline silicon layer is carried out at a temperature of 0° to 100° C.
Claim 13
Dependent Claim
26 words
The method according to claim 9, wherein the etching of the porous monocrystalline silicon layer is carried out at a temperature of 5° to 80° C.
Claim 14
Dependent Claim
26 words
The method according to claim 10, wherein the etching of the porous monocrystalline silicon layer is carried out at a temperature of 5° to 60° C.
Claim 15
Dependent Claim
42 words
The method according to claim 6 or 7, wherein the first substrate is provided by making a silicon substrate porous to form a porous monocrystalline silicon layer and by epitaxially growing a non-porous monocrystalline silicon layer on the porous monocrystalline silicon layer.
Claim 16
Dependent Claim
15 words
The method according to claim 12, wherein the silicon substrate is made porous by anodization.
Claim 17
Dependent Claim
48 words
The method according to claim 12, wherein the non-porous monocrystalline silicon layer is epitaxially grown according to a method selected from the group consisting of molecular beam epitaxy, plasma chemical vapor deposition, low pressure chemical vapor deposition, atmospheric pressure chemical vapor deposition, liquid phase growth and bias sputtering.
Claim 18
Dependent Claim
46 words
The method according to claim 6 or 7, wherein the first substrate is provided by partly making a silicon substrate porous to form a porous monocrystalline silicon layer, wherein a portion of said silicon substrate not made porous is employed as the non-porous monocrystalline silicon layer.
Claim 19
Dependent Claim
49 words
The method according to claim 14, wherein the silicon substrate is P-type, and wherein the silicon substrate is partly irradiated with protons to form a N-type silicon layer and the portion of P-type silicon of the silicon substrate is selectively made porous by anodization to provide the first substrate.
Claim 20
Dependent Claim
45 words
The method according to claim 14, wherein the silicon substrate is P-type, and wherein an intrinsic monocrystalline silicon layer is epitaxially grown on the silicon substrate and the portion of P-type silicon of the silicon substrate is selectively made porous to provide the first substrate.
Claim 21
Dependent Claim
12 words
The method according to claim 6, wherein the second substrate comprises silicon.
Claim 22
Dependent Claim
24 words
The method according to claim 6, wherein the second substrate and the insulating layer are formed by oxidizing a surface of a silicon substrate.
Claim 23
Dependent Claim
41 words
The method according to claim 6, wherein the first substrate and the insulating layer are formed by oxidizing a surface of a nonporous monocrystalline silicon layer of a substrate having a porous monocrystalline silicon layer and the non-porous monocrystalline silicon layer.
Claim 24
Dependent Claim
74 words
The method according to claim 6, wherein the insulating layer comprises a first and a second insulating layer, wherein the first substrate and the first insulating layer are formed by oxidizing a surface of a non-porous monocrystalline silicon layer of a substrate having a porous monocrystalline silicon layer and the non-porous monocrystalline silicon layer, and wherein the second substrate and the second insulating layer are formed by oxidizing a surface of a silicon substrate.
Claim 25
Dependent Claim
12 words
The method according to claim 7, wherein the second substrate comprises glass.
Claim 26
Dependent Claim
12 words
The method according to claim 7, wherein the second substrate comprises quartz.
Claim 27
Dependent Claim
12 words
A semiconductor member prepared by the method of claim 6 or 7.
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