Patent US5433168A successfully refreshed from Google Patents.
US5433168A
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US
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Method of producing semiconductor substrate
Assignee: Canon Inc
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Filing: 1993-05-14
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Granted: 1995-07-18
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Expires: 2013-05-14
Abstract
Abstract The present invention relates to a method of producing a semiconductor substrate which is suitable for an electronic device or an integrated circuit in the form of dielectric separation or having a single crystal semiconductor layer formed on an insulator. The method comprises the steps of making a silicon substrate porous, forming a silicon single crystal on the porous substrate and oxidizing the porous silicon substrate to form a semiconductor layer having good crystallinity on an insulating support, particularly a support having light transmission.
Inventors
- 👤 Takeo Yonehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 10:11
CPC Classifications
H; H10; H10P; H10P90/00; H10P90/12; H10P90/15; H10P50/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/191; H10W; H10W10/00; H10W10/10; H10W10/181; Y; Y10; Y10S; Y10S438/00; Y10S438/96
Claims Analysis
Total Claims: 81
Claim 1
Independent Claim
77 words
A method for producing a light transmitting semiconductor substrate comprising the sequential steps of: (1) making a silicon substrate porous over entire thickness region thereof, (2) forming a silicon single crystal on said porous substrate, (3) forming an antioxidant layer on said silicon single crystal (4) oxidizing said entire porous silicon substrate, wherein said substrate is light transmitting and wherein said silicon single crystal is formed in a flat and uniform layer on said light transmitting substrate.
Claim 2
Independent Claim
77 words
A method for producing a light transmitting semiconductor substrate comprising the sequential steps of: (1) making a silicon substrate porous over entire thickness region thereof, (2) forming a silicon single crystal on said porous substrate, (3) forming an antioxidant layer on said silicon single crystal (4) oxidizing said entire porous silicon substrate, wherein said substrate is light transmitting and wherein said silicon single crystal is formed in a flat and uniform layer on said light transmitting substrate.
Claim 3
Dependent Claim
29 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon single crystal formed on said substrate has a thickness of no more than 50 microns.
Claim 4
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 1, wherein said oxidizing step includes the step of heating in an atmosphere containing oxygen.
Claim 5
Dependent Claim
26 words
A method of producing a semiconductor substrate according to claim 3, wherein said oxidizing step is carried out at a pressure higher than the atmospheric pressure.
Claim 6
Dependent Claim
21 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon single crystal is formed by epitaxial growth.
Claim 7
Dependent Claim
45 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon single crystal is formed by a process selected from the group consisting of a molecular beam epitaxial process, a plasma CVD process, an optical CVD process and a bias sputtering process.
Claim 8
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 1, wherein said step of making said silicon substrate porous is an anodic etching step.
Claim 9
Dependent Claim
22 words
A method of producing a semiconductor substrate according to claim 7, wherein said anodic etching step is performed in a HF solution.
Claim 10
Dependent Claim
20 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon single crystal is of the n-type.
Claim 11
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 1, wherein the density of said porous substrate is 1.06 g/cm 3 .
Claim 12
Dependent Claim
18 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon substrate is of p-type.
Claim 13
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 11, wherein the concentration of impurities contained in said p-type silicon substrate is at least 10 13 cm -3 .
Claim 14
Independent Claim
55 words
A method of producing a semiconductor substrate comprising the steps of: providing a silicon substrate having a first side which is of the n-type, said n-type side having a thickness of no more than 50 microns and a second side, making said second side of said silicon substrate porous, and oxidizing entire porous silicon substrate.
Claim 15
Independent Claim
55 words
A method of producing a semiconductor substrate comprising the steps of: providing a silicon substrate having a first side which is of the n-type, said n-type side having a thickness of no more than 50 microns and a second side, making said second side of said silicon substrate porous, and oxidizing entire porous silicon substrate.
Claim 16
Dependent Claim
27 words
A method of producing a semiconductor substrate according to claim 13, wherein said second side of said silicon substrate which is made porous is of the p-type.
Claim 17
Dependent Claim
24 words
A method of producing a semiconductor substrate according to claim 13, wherein said n-type side has a thickness of no more than 50 microns.
Claim 18
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 13, wherein said oxidizing step includes a step of heating in an atmosphere containing oxygen.
Claim 19
Dependent Claim
26 words
A method of producing a semiconductor substrate according to claim 16, wherein said oxidizing step is carried out at a pressure higher than the atmospheric pressure.
Claim 20
Dependent Claim
29 words
A method of producing a semiconductor substrate according to claim 13, wherein said step of making said second side of said silicon substrate porous is an anodic etching step.
Claim 21
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 18, wherein said anodic etching step is carried out in a HF solution.
Claim 22
Dependent Claim
24 words
A method of producing a semiconductor substrate according to claim 13, wherein said n-type silicon is formed by irradiation of protons or epitaxial growth.
Claim 23
Dependent Claim
39 words
A method of producing a semiconductor substrate according to claim 13, further comprising the step of forming, after making said second side of said silicon substrate porous, an antioxidant layer on said n-type first side of said silicon substrate.
Claim 24
Dependent Claim
29 words
A method of producing a semiconductor substrate according to claim 21, wherein a buffer layer is provided between said antioxidant layer and said first side of said silicon substrate.
Claim 25
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 13, wherein the density of said porous substrate is 1.06 g/cm 3 .
Claim 26
Independent Claim
106 words
A method of producing a semiconductor substrate comprising the steps of: (1) making a silicon single crystal substrate entirely porous, (2) forming a first antioxidant layer on at least one side of said porous silicon, (3) oxidizing said porous silicon to leave a portion of said porous silicon on the side facing said first antioxidant layer unoxidized, (4) removing said first antioxidant layer, (5) forming a silicon single crystal layer on said unoxidized portion of said porous silicon, (6) forming a second antioxidant layer on said silicon single crystal layer, (7) oxidizing said unoxidized portion of said porous silicon, and (8) removing said second antioxidant layer.
Claim 27
Independent Claim
106 words
A method of producing a semiconductor substrate comprising the steps of: (1) making a silicon single crystal substrate entirely porous, (2) forming a first antioxidant layer on at least one side of said porous silicon, (3) oxidizing said porous silicon to leave a portion of said porous silicon on the side facing said first antioxidant layer unoxidized, (4) removing said first antioxidant layer, (5) forming a silicon single crystal layer on said unoxidized portion of said porous silicon, (6) forming a second antioxidant layer on said silicon single crystal layer, (7) oxidizing said unoxidized portion of said porous silicon, and (8) removing said second antioxidant layer.
Claim 28
Dependent Claim
26 words
A method of producing a semiconductor substrate according to claim 24, wherein said silicon single crystal layer has a thickness of no more than 50 microns.
Claim 29
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 24, wherein said oxidizing step includes the step of heating in an atmosphere containing oxygen.
Claim 30
Dependent Claim
26 words
A method of producing a semiconductor substrate according to claim 26, wherein said oxidizing step is carried out at a pressure higher than the atmospheric pressure.
Claim 31
Dependent Claim
22 words
A method of producing a semiconductor substrate according to claim 24, wherein said silicon single crystal layer is formed by epitaxial growth.
Claim 32
Dependent Claim
46 words
A method of producing a semiconductor substrate according to claim 24, wherein said silicon single crystal layer is formed by a process selected from the group consisting of a molecular beam epitaxial process, a plasma CVD process, an optical CVD process and a bias sputtering process.
Claim 33
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 24, wherein said step of making said silicon substrate porous is an anodic etching step.
Claim 34
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 30, wherein said anodic etching step is carried out in a HF solution.
Claim 35
Dependent Claim
27 words
A method of producing a semiconductor substrate according to claim 24, wherein at least one of said first and second antioxidant layers is made of silicon nitride.
Claim 36
Dependent Claim
21 words
A method of producing a semiconductor substrate according to claim 1, wherein said silicon single crystal substrate is of the n-type.
Claim 37
Dependent Claim
29 words
A method of producing a semiconductor substrate according to claim 33, wherein the concentration of impurities contained in said n-type silicon substrate is 10 13 cm -3 or more.
Claim 38
Dependent Claim
19 words
A method of producing a semiconductor substrate according to claim 24, wherein said silicon substrate is of the p-type.
Claim 39
Dependent Claim
28 words
A method of producing a semiconductor substrate according to claim 35, wherein the concentration of impurities contained in said p-type substrate is at least 10.sup. cm -3 .
Claim 40
Dependent Claim
19 words
A method of producing a semiconductor substrate according to claim 24, wherein said silicon substrate is of the n-type.
Claim 41
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 37, wherein the concentration of impurities contained in said n-type silicon substrate is at least 10 13 cm -3 .
Claim 42
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 24, wherein a buffer layer is provided between said antioxidant layer and silicon single layer.
Claim 43
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 24, wherein the density of said porous substrate is 1.06 g/cm 3 .
Claim 44
Independent Claim
86 words
A method of producing a semiconductor substrate comprising the steps of: (1) making a silicon single crystal substrate entirely porous, (2) forming an antioxidant layer on at least one side of said porous silicon, (3) oxidizing said porous silicon to leave a portion of said porous silicon on a side facing said first oxidant layer unoxidized, (4) removing the antioxidant layer, (5) forming a silicon single crystal layer on said unoxidized portion of said porous silicon, and (6) oxidizing the unoxidized portion of the porous silicon.
Claim 45
Independent Claim
86 words
A method of producing a semiconductor substrate comprising the steps of: (1) making a silicon single crystal substrate entirely porous, (2) forming an antioxidant layer on at least one side of said porous silicon, (3) oxidizing said porous silicon to leave a portion of said porous silicon on a side facing said first oxidant layer unoxidized, (4) removing the antioxidant layer, (5) forming a silicon single crystal layer on said unoxidized portion of said porous silicon, and (6) oxidizing the unoxidized portion of the porous silicon.
Claim 46
Dependent Claim
18 words
A method of producing a semiconductor substrate according to claim 41, wherein said silicon substrate is of p-type.
Claim 47
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 42, wherein the concentration of impurities contained in said p-type silicon single crystal layer is 10 19 cm -3 .
Claim 48
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 41, wherein said silicon single crystal layer has a thickness of no more than 50μ.
Claim 49
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 41, wherein the oxidizing step includes the step of heating in an atmosphere containing oxygen.
Claim 50
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 41, wherein the oxidizing step is carried out at a pressure higher than the atmosphere.
Claim 51
Dependent Claim
21 words
A method of producing a semiconductor substrate according to claim 41, wherein said silicon single crystal is formed by epitaxial growth.
Claim 52
Dependent Claim
45 words
A method of producing a semiconductor substrate according to claim 41, wherein said silicon single crystal is formed by a process selected from the group consisting of a molecular beam epitaxial process, a plasma CVD process, an optical CVD process and a bias sputtering process.
Claim 53
Dependent Claim
24 words
A method of producing a semiconductor substrate according to claim 41, wherein said step of making said silicon substrate porous is an anodization step.
Claim 54
Dependent Claim
22 words
A method of producing a semiconductor substrate according to claim 49, wherein said anodization step is carried out in a HF solution.
Claim 55
Dependent Claim
20 words
A method of producing a semiconductor substrate according to claim 41, wherein said antioxidant layer is made of silicon nitride.
Claim 56
Dependent Claim
20 words
A method of producing a semiconductor substrate according to claim 41, wherein said silicon single crystal layer is of n-type.
Claim 57
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 52, wherein the concentration of impurities contained in said n-type silicon single crystal layer is 10 13 cm -3 .
Claim 58
Dependent Claim
26 words
A method of producing a semiconductor substrate according to claim 38, wherein a buffer layer is provided between said antioxidant layer and said silicon single layer.
Claim 59
Dependent Claim
23 words
A method of producing a semiconductor substrate according to claim 41, wherein the density of said porous substrate is 1.06 g/cm 3 .
Claim 60
Independent Claim
79 words
A method of producing a semiconductor substrate, comprising the steps of: forming an antioxidant layer on at least one side of the porous silicon substrate which is made porous over its entire thickness; oxidizing said porous silicon to leave a portion of said porous silicon on the side carrying said antioxidant layer unoxidized; removing said antioxidant layer; forming a single crystal silicon on the unoxidized portion of said porous silicon; and oxidizing said unoxidized portion of said porous silicon.
Claim 61
Independent Claim
79 words
A method of producing a semiconductor substrate, comprising the steps of: forming an antioxidant layer on at least one side of the porous silicon substrate which is made porous over its entire thickness; oxidizing said porous silicon to leave a portion of said porous silicon on the side carrying said antioxidant layer unoxidized; removing said antioxidant layer; forming a single crystal silicon on the unoxidized portion of said porous silicon; and oxidizing said unoxidized portion of said porous silicon.
Claim 62
Dependent Claim
18 words
A method of producing a semiconductor substrate according to claim 56, wherein said silicon substrate is of p-type.
Claim 63
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 57, wherein the concentration of impurities contained in said p-type silicon single crystal layer is 10 19 cm -3 .
Claim 64
Dependent Claim
30 words
A method of producing a semiconductor substrate according to claim 57, wherein the concentration of impurities contained in said n-type silicon single crystal layer is 10 19 cm -3 .
Claim 65
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 56, wherein said silicon single crystal layer has a thickness of 50 microns or less.
Claim 66
Dependent Claim
24 words
A method of producing a semiconductor substrate according to claim 56, wherein said oxidizing step includes the step of heating in an atmosphere oxygen.
Claim 67
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 61, wherein said oxidizing step is carried out at a pressure higher than the atmosphere.
Claim 68
Dependent Claim
21 words
A method of producing a semiconductor substrate according to claim 56, wherein said silicon single crystal is formed by epitaxial growth.
Claim 69
Dependent Claim
45 words
A method of producing a semiconductor substrate according to claim 56, wherein said silicon single crystal is formed by a process selected from the group consisting of a molecular beam epitaxial process, a plasma CVD process, an optical CVD process and a bias sputtering process.
Claim 70
Dependent Claim
24 words
A method of producing a semiconductor substrate according to claim 56, wherein said step of making said silicon substrate porous is an anodization step.
Claim 71
Dependent Claim
22 words
A method of producing a semiconductor substrate according to claim 65, wherein said anodization step is carried out in an HF solution.
Claim 72
Dependent Claim
20 words
A method of producing a semiconductor substrate according to claim 56, wherein said antioxidant layer is made of silicon nitride.
Claim 73
Dependent Claim
20 words
A method of producing a semiconductor substrate according to claim 56, wherein said silicon single crystal layer is of n-type.
Claim 74
Independent Claim
40 words
A method of producing a semiconductor substrate comprising the steps of: forming a silicon single crystal on a silicon substrate which is made porous over its entire thickness; and oxidizing said silicon substrate, wherein said silicon substrate is light transmitting.
Claim 75
Independent Claim
40 words
A method of producing a semiconductor substrate comprising the steps of: forming a silicon single crystal on a silicon substrate which is made porous over its entire thickness; and oxidizing said silicon substrate, wherein said silicon substrate is light transmitting.
Claim 76
Dependent Claim
18 words
A method of producing a semiconductor substrate according to claim 69, wherein said silicon substrate is of p-type.
Claim 77
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 69, wherein said silicon single crystal layer has a thickness of 50 microns or less.
Claim 78
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 69, wherein said oxidizing step includes the step of heating in an atmosphere containing oxygen.
Claim 79
Dependent Claim
25 words
A method of producing a semiconductor substrate according to claim 69, wherein said oxidizing step is carried out at a pressure higher than the atmosphere.
Claim 80
Dependent Claim
21 words
A method of producing a semiconductor substrate according to claim 69, wherein said silicon single crystal is formed by epitaxial growth.
Claim 81
Dependent Claim
45 words
A method of producing a semiconductor substrate according to claim 69, wherein said silicon single crystal is formed by a process selected from the group consisting of a molecular beam epitaxial process, a plasma CVD process, an optical CVD process and a bias sputtering process.
References Cited (Backward Citations)
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