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Patent US6380099B2 successfully refreshed from Google Patents.
US6380099B2
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Porous region removing method and semiconductor substrate manufacturing method
Assignee: Canon Inc
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Filing: 1998-12-15
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Granted: 2002-04-30
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Expires: 2018-12-15
Abstract
Abstract A given planarity of the underlying layer is ensured after removal of a porous layer. In the first step, a porous layer is filled with a preprocess solution (e.g., water). In the second step, the preprocess solution filling the porous layer is replaced with an etchant (e.g., fluoric acid), and the porous layer is etched by the etchant. With this process, the time in which the porous layer is filled with the etchant is shortened to suppress variations in progress of etching.
Inventors
- 👤 Kiyofumi Sakaguchi
- 👤 Kazutaka Yanagita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:10
CPC Classifications
H; H10; H10P; H10P50/00; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0422; H10P72/0426; C; C25; C25D; C25D11/00; C25D11/02; C25D11/32; H10P50/60; H10P50/64; H10P50/642; H10P72/0424; H10P90/00; H10P90/19; H10P90/1904; H10P90/1906; H10P90/1914; H10P90/1922; H10W; H10W10/00; H10W10/10; H10W10/181
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
106 words
A porous region removing method for removing a porous region from a substrate having the porous region, comprising: the first step of filling the porous region with a first process solution having no etching function or weak etching function for a porous material; and the second step of replacing the first process solution filling the porous region with a second process solution, under the condition that the porous region is filled with the first process solution, and etching the porous region using the second process solution, the second process solution having an etching function for a porous material stronger than that of the first process solution.
Claim 2
Dependent Claim
106 words
A porous region removing method for removing a porous region from a substrate having the porous region, comprising: the first step of filling the porous region with a first process solution having no etching function or weak etching function for a porous material; and the second step of replacing the first process solution filling the porous region with a second process solution, under the condition that the porous region is filled with the first process solution, and etching the porous region using the second process solution, the second process solution having an etching function for a porous material stronger than that of the first process solution.
Claim 3
Dependent Claim
31 words
The method according to claim 1 , wherein said second step comprises replacing the first process solution filling the porous region with the second process solution to etch the porous region.
Claim 4
Dependent Claim
18 words
The method according to claim 1 , wherein said substrate to be processed essentially consists of single-crystal Si.
Claim 5
Dependent Claim
17 words
The method according to claim 1 , wherein said porous region essentially consists of an Si material.
Claim 6
Dependent Claim
21 words
The method according to claim 1 , wherein said porous region is formed by anodizing a substrate consisting of single-crystal Si.
Claim 7
Dependent Claim
43 words
The method according to claim 1 , wherein said first process solution chemically changes pore walls in the porous region, and said second process solution has the etching function not only for a porous material but also for a substance which chemically changes.
Claim 8
Dependent Claim
24 words
The method according to claim 6 , wherein said first process solution has an oxidation function for the pore walls in the porous region.
Claim 9
Dependent Claim
14 words
The method according to claim 1 , wherein said first process solution is water.
Claim 10
Independent Claim
30 words
The method according to claims 3 , wherein the first process solution contains a material selected from the group consisting of an alcohol, hydrogen peroxide, nitric acid, and hydrochloric acid.
Claim 11
Dependent Claim
15 words
The method according to claim 5 , wherein the second process solution contains hydrofluoric acid.
Claim 12
Dependent Claim
63 words
The method according to claim 5 , wherein the second process solution is a material selected from the group consisting of (a) a mixed solution prepared by adding at least one of an alcohol and hydrogen peroxide to hydrofluoric acid, (b) a mixed solution of hydrofluoric acid and nitric acid, and (c) a mixed solution of hydrofluoric acid, nitric acid, and acetic acid.
Claim 13
Dependent Claim
32 words
The method according to claim 1 , wherein an ultrasonic wave is supplied to the substrate during at least part of an overall period of execution of the first and second steps.
Claim 14
Dependent Claim
19 words
The method according to claim 1 , wherein said first step comprises supplying an ultrasonic wave to the substrate.
Claim 15
Dependent Claim
30 words
The method according to claim 1 , wherein an ultrasonic wave is supplied to the substrate during at least part of an overall period of execution of the second step.
Claim 16
Dependent Claim
47 words
The method according to claim 1 , wherein an ultrasonic wave is supplied to the substrate during at least part of an overall period of execution of the second step, in which the first process solution filling the porous region is replaced with the second process solution.
Claim 17
Dependent Claim
64 words
The method according to claim 1 , wherein said second step comprises the steps of: etching the porous region without supplying any ultrasonic wave to the substrate until the pore walls in the porous region have not more than a first thickness; and etching the porous region remaining on the substrate while supplying an ultrasonic wave to the substrate, thereby removing the porous region.
Claim 18
Dependent Claim
86 words
The method according to claim 1 , wherein said second step comprises the steps of: replacing the first process solution filling the porous region with the second process solution while supplying an ultrasonic wave to the substrate; etching the porous region without supplying any ultrasonic wave to the substrate until the pore walls in the porous region have not more than a first thickness; and etching the porous region remaining on the substrate while supplying an ultrasonic wave to the substrate, thereby removing the porous region.
Claim 19
Dependent Claim
28 words
The method according to claim 17 , wherein, in processing the substrate while supplying the ultrasonic wave to the substrate, the substrate is swung in the process solution.
Claim 20
Dependent Claim
50 words
The method according to claim 17 , wherein, in processing the substrate while supplying the ultrasonic wave to the substrate, a position of at least one of the substrate and the ultrasonic source is changed in a direction substantially parallel or perpendicular to a vibration plane of the ultrasonic wave.
Claim 21
Dependent Claim
27 words
The method according to claim 1 , wherein said first step comprises circulating the process solution to form a flow of the process solution near the substrate.
Claim 22
Dependent Claim
32 words
The method according to claim 12 , wherein supply of the ultrasonic wave to the substrate is controlled by inserting an ultrasonic wave shielding plate between the ultrasonic source and the substrate.
Claim 23
Dependent Claim
78 words
A method of manufacturing a semiconductor substrate, comprising the steps of: forming a porous layer and at least one non-porous layer on a first substrate; bonding a second substrate to the non-porous layer side of the first substrate; removing the first substrate from the bonded substrate stack to expose the porous layer on a surface of the second substrate; and removing the porous layer on the second substrate using the porous region removing method of claim 1 .
Claim 24
Dependent Claim
45 words
The method according to claim 22 , wherein the step of exposing the porous layer comprises grinding, polishing, or etching the first substrate from a lower surface side of the bonded first substrate to expose the porous layer on the surface of the second substrate.
Claim 25
Dependent Claim
37 words
The method according to claim 22 , wherein the step of exposing the porous layer comprises dividing the bonded substrate stack at the porous layer to expose the porous layer on the surface of the second substrate.
Claim 26
Dependent Claim
16 words
The method according to claim 22 , wherein said non-porous layer includes a single-crystal Si layer.
Claim 27
Dependent Claim
20 words
The method according to claim 22 wherein said non-porous layer includes a single-crystal Si layer and an Si oxide layer.
Claim 28
Dependent Claim
25 words
The method according to claim 25 , wherein said single-crystal Si layer is a layer epitaxially grown on the porous layer of the first substrate.
Claim 29
Dependent Claim
17 words
The method according to claim 22 , wherein said non-porous layer includes a single-crystal compound semiconductor layer.
Claim 30
Dependent Claim
17 words
The method according to claim 22 , wherein said second substrate essentially consists of an Si material.
Claim 31
Dependent Claim
26 words
The method according to claim 22 , wherein said second substrate has an Si oxide layer on a surface to be bonded to the first substrate.
Claim 32
Dependent Claim
15 words
The method according to claim 22 , wherein said second substrate is a transparent substrate.
Claim 33
Dependent Claim
81 words
A porous region removing apparatus for removing a porous region from a substrate having the porous region, comprising: means for executing the first step of filling the porous region with a first process solution having no etching function or weak etching function for a porous material; and means for executing the second step of replacing the first process solution filling the porous region with the second process solution having an etching function for a porous material to etch the porous region.
Claim 34
Dependent Claim
81 words
A porous region removing apparatus for removing a porous region from a substrate having the porous region, comprising: means for executing the first step of filling the porous region with a first process solution having no etching function or weak etching function for a porous material; and means for executing the second step of replacing the first process solution filling the porous region with the second process solution having an etching function for a porous material to etch the porous region.
Claim 35
Dependent Claim
27 words
The method according to claim 1 , wherein said second step comprises circulating the process solution to form a flow of the process solution near the substrate.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 2005-04-29 | 2005-10-29 | 2006-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-04-29 | 2009-10-29 | 2010-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-04-29 | 2013-10-29 | 2014-04-30 | $7700.00 | Window Closed / Lapsed |