EP0810643A2
Expired / Lapsed
EP
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Method for cleaning a porous surface of a semiconductor substrate
Assignee: Canon Inc
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Filing: 1997-05-28
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Granted: —
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Expires: 2017-05-28
Abstract
Abstract Provided is a suitable cleaning method of porous semiconductor substrate without occurrence of collapse of porous structure due to cavitation or resonance. In a cleaning method of porous surface of 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. <IMAGE>
Inventors
- 👤 Yasutomo Fujiyama
- 👤 Hideya Kumomi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 01:22
CPC Classifications
H; H10; H10P; H10P70/00; H10P70/10; H10P70/15; H10P52/00; B; B08; B08B; B08B3/00; B08B3/04; B08B3/10; B08B3/12; H10P50/00; H10P50/60; H10P50/61; H10P50/613
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
63 words
A cleaning method of porous surface for cleaning a porous surface of a substrate having the porous structure at least in the surface thereof, wherein cleaning for removing dust particles adhering to the porous surface of said 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.
Claim 2
Dependent Claim
58 words
The cleaning method of porous surface according to Claim 1, wherein the surface of the substrate to be cleaned has such structure that apertures of many pores are exposed and internal wall surfaces of the pores have such structure that a material of the porous structure is exposed or is covered with a material of a different kind.
Claim 3
Dependent Claim
32 words
The cleaning method of porous surface according to Claim 1 or Claim 2, wherein cleaning takes place by immersing said substrate in a pure water bath and superimposing said high-frequency wave thereon.
Claim 4
Dependent Claim
34 words
The cleaning method of porous surface according to Claim 3, wherein cleaning takes place by superimposing said high-frequency wave in parallel to the porous surface of the substrate immersed in said pure water bath.
Claim 5
Dependent Claim
33 words
The cleaning method of porous surface according to Claim 3 or Claim 4, wherein said substrate under the high-frequency cleaning as immersed in said pure water bath is lifted intermittently out of liquid.
Claim 6
Dependent Claim
42 words
The cleaning method of porous surface according to Claim 1 or Claim 2, wherein cleaning takes place by blowing a pure water shower with a high-frequency wave superimposed on pure water, against the porous surface of said substrate while rotating said substrate.
Claim 7
Dependent Claim
49 words
A cleaning method of substrate, wherein cleaning for removing dust particles adhering to a surface of a substrate takes place with pure water from which dissolved gas is deaerated until a concentration of the dissolved gas becomes 5 ppm or less and on which an ultrasonic wave is superimposed.
Claim 8
Dependent Claim
35 words
The cleaning method of porous surface according to Claim 1, wherein said pure water is pure water from which dissolved gas is deaerated until a concentration of the dissolved gas becomes 5 ppm or less.
Claim 9
Dependent Claim
54 words
The cleaning method of porous surface according to Claim 8, wherein said substrate is cleaned by immersing the substrate in a pure water bath having the pure water from which the dissolved gas is deaerated until the concentration of the dissolved gas becomes 5 ppm or less and superimposing said high-frequency ultrasonic wave thereon.
Claim 10
Dependent Claim
59 words
The cleaning method of porous surface according to Claim 8, wherein cleaning takes place by blowing a pure water shower from which the dissolved gas is deaerated until the concentration of the dissolved gas becomes 5 ppm or less and on which said high-frequency ultrasonic wave is superimposed, against the porous surface of the substrate while rotating said substrate.
Claim 11
Dependent Claim
24 words
The cleaning method of porous surface according to Claim 1, wherein said porous surface of the substrate is processed so as to become hydrophilic.
Claim 12
Dependent Claim
80 words
A cleaning method of porous surface for cleaning a porous surface of a substrate having the porous structure at least in the surface thereof, wherein cleaning for removing dust particles adhering to the surface of said substrate takes place by processing the porous surface of said substrate so as to become hydrophilic and superimposing a high-frequency ultrasonic wave with a frequency in the range of from 600 kHz to 2 MHz on a liquid for cleaning of the porous surface.
Claim 13
Dependent Claim
42 words
The cleaning method of porous surface according to Claim 11 or 12, wherein the hydrophilic process of said porous surface is a process for forming an oxide film over the substrate surface and over internal walls of pores of the porous structure.
Claim 14
Dependent Claim
36 words
The cleaning method of porous surface according to Claim 11, wherein the hydrophilic process of said porous surface is a process for immersing said substrate in ozone pure water in which ozone dissolves in pure water.
Claim 15
Dependent Claim
34 words
The cleaning method of porous surface according to Claim 11, wherein the hydrophilic process of said porous surface is a process for immersing said substrate in a hydrogen peroxide solution diluted with pure water.
Claim 16
Dependent Claim
24 words
The cleaning method of porous surface according to Claim 12, wherein said liquid is ozone pure water in which ozone dissolves in pure water.
Claim 17
Dependent Claim
22 words
The cleaning method of porous surface according to Claim 12, wherein said liquid is a hydrogen peroxide solution diluted with pure water.
Claim 18
Dependent Claim
66 words
The cleaning method of porous surface according to either one of Claims 11 to 17, wherein the hydrophilic process of the porous surface is a process for forming an oxide film over the substrate surface and over internal walls of pores of the porous structure and at least the oxide film over the substrate surface is removed after cleaning of the porous surface of said substrate.
Claim 19
Independent Claim
45 words
A method of manufacturing a semiconductor device comprising steps of: cleaning the porous surface of a substrate by the method of any one of the preceding claims; preparing the cleaned substrate for semiconductor device processing; and processing the prepared substrate to produce a semiconductor device.
Claim 20
Dependent Claim
128 words
The method of claim 19 wherein the cleaned substrate comprises successive layers of non-porous and porous silicon, respectively, and the cleaned substrate is prepared by steps of: forming a surface film of silicon oxide at the pore walls and exposed surface of said porous silicon layer; removing said oxide film formed at the surface of said porous silicon layer; growing an epitaxial layer of non-porous silicon on the surface of said porous silicon layer; forming a surface film of silicon oxide on said epitaxial layer; bonding a second substrate to said surface film of silicon oxide formed on said epitaxial layer; and removing said layers of non-porous and porous silicon comprising said cleaned substrate, to expose a surface of said epitaxial layer for the subsequent semiconductor device processing.
References Cited (Backward Citations)
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