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US6058945A Expired / Lapsed US ⏱️ 0.0 years remaining

Cleaning methods of porous surface and semiconductor surface

Assignee: Canon Inc
•
Filing: 1997-09-03
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Granted: 2000-05-09
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Expires: 2017-09-03
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Abstract

Abstract Provided is a suitable cleaning method of a porous semiconductor substrate without collapse of the porous structure due to cavitation or resonance. In a cleaning method of a porous surface of a semiconductor substrate having the porous structure at least in the surface, cleaning for removing dust particles adhering to the porous surface of the substrate takes place with pure water on which a high-frequency wave with a frequency in the range of from 600 kHz to 2 MHz is superimposed.

Inventors

  • 👤 Yasutomo Fujiyama
  • 👤 Hideya Kumomi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 11:30
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; B; B08; B08B; B08B3/00; B08B3/04; B08B3/10; B08B3/12; H10P50/00; H10P50/60; H10P50/61; H10P50/613; Y; Y10; Y10S; Y10S134/00; Y10S134/902

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 74 words
A cleaning method for a member having a porous surface comprising the steps of: immersing the member having the porous surface in pure water, wherein the pure water is deaerated to provide a concentration of nitrogen dissolved in the pure water of 5 ppm or less; and applying a high-frequency wave ranging from 600 kHz to 2 MHz to the pure water in a progressive direction parallel to the porous surface of the member.
Claim 2
Dependent Claim 74 words
A cleaning method for a member having a porous surface comprising the steps of: immersing the member having the porous surface in pure water, wherein the pure water is deaerated to provide a concentration of nitrogen dissolved in the pure water of 5 ppm or less; and applying a high-frequency wave ranging from 600 kHz to 2 MHz to the pure water in a progressive direction parallel to the porous surface of the member.
Claim 3
Dependent Claim 32 words
The cleaning method according to claim 1 further comprising the step of anodizing a member comprised of a non-porous material in a HF solution to make the surface of the member porous.
Claim 4
Dependent Claim 29 words
The cleaning method according to claim 1, wherein said pure water is deaerated to provide a concentration of oxygen dissolved in the pure water of 5 ppm or less.
Claim 5
Dependent Claim 33 words
The cleaning method according to claim 1, wherein said pure water is deaerated to provide a concentration of oxygen or carbon dioxide dissolved in the pure water of 5 ppm or less, respectively.
Claim 6
Dependent Claim 24 words
The cleaning method according to claim 1 further comprising the step of intermittently removing from the pure water said member having the porous surface.
Claim 7
Dependent Claim 107 words
A cleaning method for a member having a porous surface comprising the steps of: anodizing a member comprised of a non-porous material in a HF solution to make the surface porous; treating the porous surface of the member so as to make the porous surface hydrophilic; immersing the member having the hydrophilic porous surface in pure water, wherein the pure water is deaerated to provide a concentration of nitrogen dissolved in the cure water of 5 ppm or less; and applying a high-frequency wave ranging from 600 kHz to 2 MHz to the pure water in a progressive direction parallel to the porous surface of the member.
Claim 8
Dependent Claim 107 words
A cleaning method for a member having a porous surface comprising the steps of: anodizing a member comprised of a non-porous material in a HF solution to make the surface porous; treating the porous surface of the member so as to make the porous surface hydrophilic; immersing the member having the hydrophilic porous surface in pure water, wherein the pure water is deaerated to provide a concentration of nitrogen dissolved in the cure water of 5 ppm or less; and applying a high-frequency wave ranging from 600 kHz to 2 MHz to the pure water in a progressive direction parallel to the porous surface of the member.
Claim 9
Dependent Claim 20 words
The cleaning method according to claim 6, wherein said treating step includes forming an oxide film on said porous surface.
Claim 10
Dependent Claim 24 words
The cleaning method according to claim 6, wherein said treating step includes immersing said member having the porous surface in pure water containing ozone.
Claim 11
Dependent Claim 23 words
The cleaning method according to claim 6, wherein said treating step includes immersing said member having the porous surface in hydrogen peroxide solution.

References Cited (Backward Citations)

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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) 2003-05-09 2003-11-08 2004-05-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2007-05-09 2007-11-08 2008-05-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2011-05-09 2011-11-08 2012-05-09 $7700.00 Window Closed / Lapsed

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