US5679475A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor substrate and process for preparing the same
Assignee: Canon Inc
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Filing: 1995-01-04
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Granted: 1997-10-21
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Expires: 2015-01-04
Abstract
Abstract A process for preparing a semiconductor substrate comprises a step of porousifying a silicon monocrystalline substrate to form a porous layer, a step of making a silicon monocrystalline thin film to epitaxially grow on a surface of the porous layer, a step of oxidizing the surface of the epitaxial growth layer, a step of forming a deposited film on the oxidized surface, thereby obtaining a first substrate, a step of closely contacting the deposited film of the first substrate to a second substrate, a step of heat treating the closely contacted substrates and a step of selectively etching the porous layer.
Inventors
- 👤 Kenji Yamagata
- 👤 Takao Yonehara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:39
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/60; H10P50/64; H10P50/642; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1914; H10P90/1922; H10W; H10W10/00; H10W10/10; H10W10/181; H10P72/00; H10P72/70; H10P72/74; H10P72/7432; Y; Y10; Y10S; Y10S438/00; Y10S438/96; Y10S438/977; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249967
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
99 words
A semiconductor substrate formed by: (a) porousifying a silicon monocrystalline substrate to form a porous layer; (b) epitaxially growing a silicon monocrystalline thin film on a surface of the porous layer; (c) oxidizing the surface of the epitaxially grown layer; (d) forming a deposited film on the oxidized surface, thereby forming a first substrate; (e) contacting the deposited film of the first substrate with a second substrate; (f) heat treating the contacted substrates, wherein as a result of said steps (e) and (f) the first substrate is bonded to the second substrate; and (g) selectively etching the porous layer.
Claim 2
Dependent Claim
99 words
A semiconductor substrate formed by: (a) porousifying a silicon monocrystalline substrate to form a porous layer; (b) epitaxially growing a silicon monocrystalline thin film on a surface of the porous layer; (c) oxidizing the surface of the epitaxially grown layer; (d) forming a deposited film on the oxidized surface, thereby forming a first substrate; (e) contacting the deposited film of the first substrate with a second substrate; (f) heat treating the contacted substrates, wherein as a result of said steps (e) and (f) the first substrate is bonded to the second substrate; and (g) selectively etching the porous layer.
Claim 3
Dependent Claim
17 words
The semiconductor substrate according to claim 1, wherein the deposited film is a film containing silicon atoms.
Claim 4
Dependent Claim
35 words
The semiconductor substrate according to claim 2, wherein the deposited film is selected from the group consisting of a polycrystalline silicon film, an amorphous silicon film, a silicon oxide film and a silicon nitride film.
Claim 5
Dependent Claim
17 words
The semiconductor substrate according to claim 1, wherein the deposited film is formed by chemical vapor deposition.
Claim 6
Dependent Claim
18 words
The semiconductor substrate according to claim 1, wherein the deposited film is at least 2 μm in thickness.
Claim 7
Dependent Claim
18 words
The semiconductor substrate according to claim 5, wherein the deposited film is at least 10 μm in thickness.
Claim 8
Dependent Claim
23 words
The semiconductor substrate according to claim 1, wherein the oxidized film of step (c) is from 0.5 μm to 1.0 μm in thickness.
Claim 9
Dependent Claim
15 words
The semiconductor substrate according to claim 1, wherein the second substrate is a transparent substrate.
Claim 10
Dependent Claim
13 words
The semiconductor substrate according to claim 8, wherein the second substrate comprises quartz.
Claim 11
Dependent Claim
13 words
The semiconductor substrate according to claim 1, wherein the second substrate comprises silicon.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2000-10-20 | 2001-04-21 | 2001-10-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-10-20 | 2005-04-21 | 2005-10-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-10-20 | 2009-04-21 | 2009-10-21 | $7700.00 | Window Closed / Lapsed |