US6143628A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor substrate and method of manufacturing the same
Assignee: Canon Inc
•
Filing: 1998-03-25
•
Granted: 2000-11-07
•
Expires: 2018-03-25
Abstract
Abstract A manufacturing method excellent in controllability, productivity and economics of a high-quality SOI wafer and a wafer manufactured by that method are provided. After wafer bonding, separation is made on an interface of a high porosity layer in a porous region including a low porosity layer and the high porosity layer in a surface formed on a main surface side of a first Si substrate 2 to transfer a non-porous layer onto a second substrate. After separation at the high porosity layer, a residual low porosity thin layer is made non-porous by a smoothing process such as hydrogen annealing without using selective etching.
Inventors
- 👤 Nobuhiko Sato
- 👤 Takao Yonehara
- 👤 Kiyofumi Sakaguchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:14
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/01; H10D48/04; H10D48/042; H10P; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1914
Claims Analysis
Total Claims: 84
Claim 1
Independent Claim
148 words
A method of manufacturing a semiconductor substrate comprising the steps of: preparing a first substrate having a porous region including at least two layers different in porosity and a non-porous layer formed on said porous region; bonding a surface of said non-porous layer of said first substrate to a surface of a second substrate; separating said first and second substrates from each other to transfer said non-porous layer to said second substrate; and removing the residual portion of the porous region remaining on a separation surface of said second substrate or making the residual portion non-porous to smooth said separation surface; wherein the step of preparing said first substrate comprises a step of forming a first porous layer of 1 μm or less thickness, a second porous layer adjacent to said first porous layer and high in porosity, and said non-porous layer adjacent to said first porous layer.
Claim 2
Independent Claim
148 words
A method of manufacturing a semiconductor substrate comprising the steps of: preparing a first substrate having a porous region including at least two layers different in porosity and a non-porous layer formed on said porous region; bonding a surface of said non-porous layer of said first substrate to a surface of a second substrate; separating said first and second substrates from each other to transfer said non-porous layer to said second substrate; and removing the residual portion of the porous region remaining on a separation surface of said second substrate or making the residual portion non-porous to smooth said separation surface; wherein the step of preparing said first substrate comprises a step of forming a first porous layer of 1 μm or less thickness, a second porous layer adjacent to said first porous layer and high in porosity, and said non-porous layer adjacent to said first porous layer.
Claim 3
Dependent Claim
48 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein the step of forming said non-porous layer comprises a step of making a surface side portion of said first porous layer non-porous, and/or a step of forming a non-porous layer on said first porous layer.
Claim 4
Dependent Claim
52 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein the step of forming said first porous layer comprises a step of making, after forming a porous layer, a surface side portion of said porous layer non-porous to make a remaining porous layer 1 μm or less in thickness.
Claim 5
Dependent Claim
25 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second porous layer is thickened more than said first porous layer.
Claim 6
Dependent Claim
46 words
A method of manufacturing a semiconductor substrate as claimed in claim 1 or 4, wherein after a second porous layer thinner than said first porous layer is formed, a surface side portion of said first porous layer is made non-porous to thin said first porous layer.
Claim 7
Dependent Claim
48 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, further comprising a step of forming a third porous layer thicker and lower in porosity than said second porous layer on a side opposite to said first porous layer with respect to said second porous layer.
Claim 8
Dependent Claim
36 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said separation surface smoothing step is conducted by a heat treatment in a non-oxidizing atmosphere without using anyone of selective etching and polishing.
Claim 9
Dependent Claim
32 words
A method of manufacturing a semiconductor substrate as claimed in claim 6, wherein said non-oxidizing atmosphere is hydrogen, an inert gas or a mixture atmosphere consisting of hydrogen and the inert gas.
Claim 10
Dependent Claim
37 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein the step of smoothing said separation surface is conducted by a heat treatment in vacuum without using any one of selective etching and polishing.
Claim 11
Dependent Claim
21 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said porous region is made of single crystal.
Claim 12
Dependent Claim
22 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said porous region is a single crystal Si layer.
Claim 13
Dependent Claim
23 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said porous region is formed by anodizing said first substrate.
Claim 14
Dependent Claim
61 words
A method of manufacturing a semiconductor substrate as claimed in claim 12, wherein said first porous layer and said second porous layer are formed by anodization and selectively formed according to the kind and concentration of impurities in the first substrate, a current density, the composition and temperature of a chemical agent at the time of anodization or a combination thereof.
Claim 15
Dependent Claim
41 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein after the porous region is formed on one surface of the first substrate, said second porous layer is formed at an ion projection range position by ion implantation.
Claim 16
Dependent Claim
48 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein a side wall surface of pores in the porous region is oxidized to such a degree that a porous crystal structure remains in the interior of the side wall before the non-porous layer is formed.
Claim 17
Dependent Claim
47 words
A method of manufacturing a semiconductor substrate as claimed in claim 15, wherein an oxide film formed on the side wall of the pores in the surface of said porous region and in the vicinity of the surface thereof is removed before said non-porous layer is formed.
Claim 18
Dependent Claim
42 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said non-porous layer includes a portion where the surface of said first porous layer is made non-porous by a heat treatment in a non-oxidizing atmosphere or in a vacuum.
Claim 19
Dependent Claim
54 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said non-porous layer includes a portion where the surface of said first porous layer is made non-porous by a heat treatment in a non-oxidizing atmosphere or in a vacuum, and an oxide film formed on the surface of said non-porous layer.
Claim 20
Dependent Claim
29 words
A method of manufacturing a semiconductor substrate as claimed in claim 17 or 18, wherein said non-oxidizing atmosphere is hydrogen, an inert gas or a mixture gas atmosphere thereof.
Claim 21
Dependent Claim
24 words
A method of manufacturing a semiconductor substrate as claimed in claim 17 or 18, wherein said non-oxidizing atmosphere includes a small amount of Si.
Claim 22
Dependent Claim
32 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said non-porous layer is formed by epitaxy on the basis of a crystal orientation of said first porous layer.
Claim 23
Dependent Claim
48 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said non-porous layer consists of a single crystal layer formed by epitaxy on the basis of a crystal orientation of said first porous layer, and an oxide film layer formed above said single crystal layer.
Claim 24
Dependent Claim
27 words
A method of manufacturing a semiconductor substrate as claimed in claim 21 or 22, wherein said non-porous layer formed by epitaxy is a single crystal Si layer.
Claim 25
Dependent Claim
28 words
A method of manufacturing a semiconductor substrate as claimed in claim 21 or 22, wherein said non-porous layer formed by epitaxy has a single crystal compound semiconductor layer.
Claim 26
Dependent Claim
30 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said non-porous layer consists of a plurality of layers different in electric conductive type or impurity concentration.
Claim 27
Dependent Claim
21 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said first substrate after being separated is reused.
Claim 28
Dependent Claim
23 words
A method of manufacturing a semiconductor substrate as claimed in claim 26, wherein a pre-treatment for reusing consists of only a smoothing process.
Claim 29
Dependent Claim
36 words
A method of manufacturing a semiconductor substrate as claimed in claim 26, wherein a pre-treatment for reusing comprises a process of removing a residual portion of the porous region remaining after separation and a flattening process.
Claim 30
Dependent Claim
41 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said separating step is conducted by any one of pressurizing, tension, shearing, wedge insertion, a heat treatment, oxidation, wave motion application and wire cutting or a combination thereof.
Claim 31
Dependent Claim
20 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second substrate is made of Si.
Claim 32
Dependent Claim
38 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second substrate is formed of an Si substrate, and an insulating film is formed on at least one of the surfaces to be bonded.
Claim 33
Dependent Claim
23 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second substrate is formed of a light transmissive substrate.
Claim 34
Dependent Claim
25 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said first porous layer is of 0.5 μm or less in thickness.
Claim 35
Dependent Claim
25 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second porous layer has the highest porosity in the porous region.
Claim 36
Dependent Claim
31 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said porous region consists of only two layers of the first porous layer and the second porous layer.
Claim 37
Dependent Claim
25 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said second porous layer is of 1 μm or less in thickness.
Claim 38
Dependent Claim
25 words
A method of manufacturing a semiconductor substrate as claimed in claim 36, wherein said second porous layer is of 0.5 μm or less in thickness.
Claim 39
Dependent Claim
24 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein said porous region is of 2 μm or less in thickness.
Claim 40
Dependent Claim
56 words
A method of manufacturing a semiconductor substrate as claimed in claim 1, wherein in the step of forming said first porous layer, after a porous layer of 1 μm or less thickness is formed, a surface side portion of said porous layer is made non-porous to make the remaining porous layer 0.5 μm or less thickness.
Claim 41
Dependent Claim
17 words
A semiconductor substrate manufactured by a method of manufacturing a semiconductor substrate as claimed in claim 1.
Claim 42
Independent Claim
120 words
A method of manufacturing a semiconductor article comprising the steps of: preparing a first substrate having a porous region including at least two layers different in porosity and a non-porous layer formed on said porous region; bonding a surface of said non-porous layer of said first substrate to a surface of a second substrate; and separating said first and second substrates from each other to transfer said non-porous layer to said second substrate; wherein the step of preparing said first substrate comprises a step of forming a first porous layer of 1 μm or less thickness, a second porous layer adjacent to said first porous layer and high in porosity, and said non-porous layer adjacent to said first porous layer.
Claim 43
Independent Claim
120 words
A method of manufacturing a semiconductor article comprising the steps of: preparing a first substrate having a porous region including at least two layers different in porosity and a non-porous layer formed on said porous region; bonding a surface of said non-porous layer of said first substrate to a surface of a second substrate; and separating said first and second substrates from each other to transfer said non-porous layer to said second substrate; wherein the step of preparing said first substrate comprises a step of forming a first porous layer of 1 μm or less thickness, a second porous layer adjacent to said first porous layer and high in porosity, and said non-porous layer adjacent to said first porous layer.
Claim 44
Dependent Claim
48 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein the step of forming said non-porous layer comprises a step of making a surface side portion of said first porous layer non-porous, and/or a step of forming a non-porous layer on said first porous layer.
Claim 45
Dependent Claim
52 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein the step of forming said first porous layer comprises a step of making, after forming a porous layer, a surface side portion of said porous layer non-porous to make a remaining porous layer 1 μm or less in thickness.
Claim 46
Dependent Claim
25 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said second porous layer is thickened more than said first porous layer.
Claim 47
Dependent Claim
46 words
A method of manufacturing a semiconductor article as claimed in claim 41 or 44, wherein after a second porous layer thinner than said first porous layer is formed, a surface side portion of said first porous layer is made non-porous to thin said first porous layer.
Claim 48
Dependent Claim
48 words
A method of manufacturing a semiconductor article as claimed in claim 41, further comprising a step of forming a third porous layer thicker and lower in porosity than said second porous layer on a side opposite to said first porous layer with respect to said second porous layer.
Claim 49
Dependent Claim
37 words
A method of manufacturing a semiconductor article as claimed in claim 41, further comprising a separation surface smoothing step conducted by a heat treatment in a non-oxidizing atmosphere without using any one of selective etching and polishing.
Claim 50
Dependent Claim
32 words
A method of manufacturing a semiconductor article as claimed in claim 46, wherein said non-oxidizing atmosphere is hydrogen, an inert gas or a mixture atmosphere consisting of hydrogen and the inert gas.
Claim 51
Dependent Claim
37 words
A method of manufacturing a semiconductor article as claimed in claim 41, further comprising a step of smoothing a separation surface conducted by a heat treatment in vacuum without using any one of selective etching and polishing.
Claim 52
Dependent Claim
21 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said porous region is made of single crystal.
Claim 53
Dependent Claim
22 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said porous region is a single crystal Si layer.
Claim 54
Dependent Claim
23 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said porous region is formed by anodizing said first substrate.
Claim 55
Dependent Claim
61 words
A method of manufacturing a semiconductor article as claimed in claim 52, wherein said first porous layer and said second porous layer are formed by anodization and selectively formed according to the kind and concentration of impurities in the first substrate, a current density, the composition and temperature of a chemical agent at the time of anodization or a combination thereof.
Claim 56
Dependent Claim
41 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein after the porous region is formed on one surface of the first substrate, said second porous layer is formed at an ion projection range position by ion implantation.
Claim 57
Dependent Claim
48 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein a side wall surface of pores in the porous region is oxidized to such a degree that a porous crystal structure remains in the interior of the side wall before the non-porous layer is formed.
Claim 58
Dependent Claim
47 words
A method of manufacturing a semiconductor article as claimed in claim 55, wherein an oxide film formed on the side wall of the pores in the surface of said porous region and in the vicinity of the surface thereof is removed before said non-porous layer is formed.
Claim 59
Dependent Claim
42 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said non-porous layer includes a portion where the surface of said first porous layer is made non-porous by a heat treatment in a non-oxidizing atmosphere or in a vacuum.
Claim 60
Dependent Claim
54 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said non-porous layer includes a portion where the surface of said first porous layer is made non-porous by a heat treatment in a non-oxidizing atmosphere or in a vacuum, and an oxide film formed on the surface of said non-porous layer.
Claim 61
Dependent Claim
29 words
A method of manufacturing a semiconductor article as claimed in claim 57 or 58, wherein said non-oxidizing atmosphere is hydrogen, an inert gas or a mixture gas atmosphere thereof.
Claim 62
Dependent Claim
24 words
A method of manufacturing a semiconductor article as claimed in claim 57 or 58, wherein said non-oxidizing atmosphere includes a small amount of Si.
Claim 63
Dependent Claim
32 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said non-porous layer is formed by epitaxy on the basis of a crystal orientation of said first porous layer.
Claim 64
Dependent Claim
48 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said non-porous layer consists of a single crystal layer formed by epitaxy on the basis of a crystal orientation of said first porous layer, and an oxide film layer formed above said single crystal layer.
Claim 65
Dependent Claim
27 words
A method of manufacturing a semiconductor article as claimed in claim 61 or 62, wherein said non-porous layer formed by epitaxy is a single crystal Si layer.
Claim 66
Dependent Claim
28 words
A method of manufacturing a semiconductor article as claimed in claim 61 or 62, wherein said non-porous layer formed by epitaxy has a single crystal compound semiconductor layer.
Claim 67
Dependent Claim
30 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said non-porous layer consists of a plurality of layers different in electric conductive type or impurity concentration.
Claim 68
Dependent Claim
21 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said first substrate after being separated is reused.
Claim 69
Dependent Claim
23 words
A method of manufacturing a semiconductor article as claimed in claim 66, wherein a pre-treatment for reusing consists of only a smoothing process.
Claim 70
Dependent Claim
36 words
A method of manufacturing a semiconductor article as claimed in claim 66, wherein a pre-treatment for reusing comprises a process of removing a residual portion of the porous region remaining after separation and a flattening process.
Claim 71
Dependent Claim
41 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said separating step is conducted by any one of pressurizing, tension, shearing, wedge insertion, a heat treatment, oxidation, wave motion application and wire cutting or a combination thereof.
Claim 72
Dependent Claim
20 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said second substrate is made of Si.
Claim 73
Independent Claim
38 words
A method of manufacturing a semiconductor article as claimed in clam 41, wherein said second substrate is formed on an Si substrate, and an insulating film is formed on at least one of the surfaces to be bonded.
Claim 74
Dependent Claim
23 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said second substrate is formed of a light transmissive substrate.
Claim 75
Dependent Claim
25 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said first porous layer is of 0.5 μm or less in thickness.
Claim 76
Dependent Claim
25 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said second porous layer has the highest porosity in the porous region.
Claim 77
Dependent Claim
31 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said porous region consists of only two layers of the first porous layer and the second porous layer.
Claim 78
Dependent Claim
25 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said second porous layer is of 1 μm or less in thickness.
Claim 79
Dependent Claim
25 words
A method of manufacturing a semiconductor article as claimed in claim 76, wherein said second porous layer is of 0.5 μm or less in thickness.
Claim 80
Dependent Claim
24 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein said porous region is of 2 μm or less in thickness.
Claim 81
Dependent Claim
56 words
A method of manufacturing a semiconductor article as claimed in claim 41, wherein in the step of forming said first porous layer, after a porous layer of 1 μm or less thickness is formed, a surface side portion of said porous layer is made non-porous to make the remaining porous layer 0.5 μm or less thickness.
Claim 82
Dependent Claim
17 words
A semiconductor article manufactured by a method of manufacturing a semiconductor article as claimed in claim 41.
Claim 83
Independent Claim
25 words
A method of manufacturing a semiconductor article as claimed in clam 41, further comprising a step of smoothing a separation surface of the second substrate.
Claim 84
Dependent Claim
41 words
A method of manufacturing a semiconductor article as claimed in claim 81, wherein the smoothing step comprises a step of removing the residual portion of the porous region, and/or a step of making the residual portion of the porous region non-porous.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-11-07 | 2004-05-08 | 2004-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-07 | 2008-05-08 | 2008-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-07 | 2012-05-08 | 2012-11-07 | $7700.00 | Window Closed / Lapsed |