EP0476676A2
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EP
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Thin film deposition method
Assignee: Canon Anelva Corp
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Filing: 1991-09-20
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Granted: —
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Expires: 2011-09-20
Abstract
Abstract A thin film deposition method consists of depositing a thin film on a wafer by supplying a reactant gas molecules toward and onto the wafer within a vacuum vessel or chamber. The pressure within the vacuum vessel is set to the pressure under which the mean free path (d) of the molecules contained in the supplied reactant gas can be longer than the shortest distance (L) between the wafer and the wall of the vacuum vessel exposed to the vacuum side, or d > L. The temperature of the wafer is set to the temperature (T sub) at which the reactant gas can cause substantially the thermally decomposing reaction. The temperature of the vacuum side-exposed wall of the vacuum vessel (T wall) is set to a temperature range having the lower limit higher than the temperature (T vap) at which the saturated vapor pressure can be maintained to be equal to the partial pressure of the molecules contained in the reactant gas, and having the upper limit lower than the temperature of the wafer (T sub), or T vap < T wall < T sub.
Inventors
- 👤 Ken-Ichi C/O Anelva Corporation Aketagawa
- 👤 Junro C/O Anelva Corporation Sakai
- 👤 Toru C/O Nec Corporation Tatsumi
- 👤 Shun-Ichi C/O Anelva Corporation Murakami
- 👤 Hiroyoshi C/O Anelva Corporation Murota
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 19:58
CPC Classifications
H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; C; C23; C23C; C23C16/00; C23C16/44; C23C16/455; C23C16/45502; C23C16/4551; C30; C30B; C30B25/00; C30B25/02; C30B25/16; C30B29/00; C30B29/02; C30B29/06; C30B29/08; H10P14/40; H10P14/42; H10P14/43; H10P95/00; H10P95/90
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
238 words
A thin film deposition method which includes depositing a thin film on a wafer surface by supplying a reactant gas molecules toward and onto the wafer within a vacuum vessel or chamber, said method including: (i) evacuating the vacuum vessel or chamber until the pressure within the vacuum vessel or chamber reaches a predetermined vacuum pressure range; (ii) supplying a reactant gas containing at least one kind of molecules into the vacuum vessel; (iii) setting the pressure within the vacuum vessel to a pressure under which the mean free path "d" of the molecules contained in the reactant gas being supplied can be longer than the shortest distance "L" between the wafer and the wall of the vacuum vessel or chamber exposed to the vacuum side, or d > L; (iv) setting the temperature of the wafer (T sub) to a temperature at which the reactant gas being supplied can cause substantially thermally decomposing reaction; and (v) setting the temperature of the vacuum side-exposed wall of the vacuum vessel or chamber (T wall) to a temperature range having the lower limit higher than the temperature (T vap) at which a saturated vapor pressure can be maintained to the same value as the partial pressure of the molecules contained in the reactant gas as set in step(iii), and the upper limit lower than the temperature of the wafer (T sub), or T vap < T wall < T sub.
Claim 2
Dependent Claim
30 words
The thin film deposition method as defined in Claim 1, wherein the thin film being deposited on the wafer surface is a thin film being deposited by the epitaxial growth.
Claim 3
Dependent Claim
37 words
The thin film deposition method as defined in Claim 1 or 2, wherein the reactant gas being supplied is Si₂H₆ gas, and wherein the thin film being deposited on the wafer surface is an epitaxial silicon film.
Claim 4
Dependent Claim
42 words
The thin film deposition method as defined in one of claims 1-3, wherein the pressure within the vacuum vessel or chamber is maintained to about 1.5 x 10⁻² Torr after the reactant gas has been supplied into the vacuum vessel or chamber.
Claim 5
Dependent Claim
32 words
The thin film deposition method as defined in one of claims 1-4, wherein the temperature of the vacuum side-exposed wall of the vacuum vessel or chamber (T wall) is about 10 °C.
Claim 6
Dependent Claim
39 words
The thin film deposition method as defined in one of claims 1-5, wherein the vacuum side-exposed wall is a shroud mounted inside the vacuum vessel or chamber, said shroud being maintained to a specific temperature by circulating water therethrough.
Claim 7
Dependent Claim
31 words
The thin film deposition method as defined in one of claims 1-6, wherein the pressure within the vacuum vessel or chamber as set in step (i) is 2 x 10⁻⁹ Torr.
Claim 8
Dependent Claim
38 words
The thin film deposition method as defined in one of claims 1-7, wherein the pressure within the vacuum vessel or chamber as set in step (i) is established during the baking process for the vacuum vessel or chamber.
Claim 9
Dependent Claim
45 words
The thin film deposition method as defined in one of claims 1-8, wherein the reactant gas being supplied is stopped at the moment that a thin film being deposited on the wafer reaches a thickness as required after a specific period of time has elapsed.
Claim 10
Dependent Claim
255 words
The thin film deposition method as defined in one of claims 1-8, said method further including: (vi) stopping the reactant gas being supplied in step (ii) at the moment that a thin film has reached a thickness as required, and supplying a reactant gas containing a different kind of molecules from those contained in the reactant gas supplied in step (ii); (vii) setting the pressure within the vacuum vessel to a pressure under which the mean free path "d" of the molecules contained in the reactant gas being supplied in step (vi) can be longer than the shortest distance "L" between the wafer and the wall of the vacuum vessel or chamber exposed to the vacuum side, or d > L; (viii) setting the temperature of th wafer (T sub) to a temperature at which the reactant gas being supplied in step (vi) can cause substantially thermally decomposing reaction; (ix) setting the temperature of the vacuum side-exposed wall of the vacuum vessel or chamber (T wall) to a temperature range having the lower limit higher than the temperature (T vap) at which a saturated vapor pressure can be maintained to the same value as the partial pressure of the molecules contained in the reactant gas as set in step (vii), and the upper limit lower than the temperature of the wafer (T sub), or T vap < T wall < T sub; (x) stopping the reactant gas being supplied in step (vi) at the moment that a thin film has reached a thickness as required.
Claim 11
Dependent Claim
18 words
The thin film deposition method as defined in Claim 10, wherein the steps (ii) through (x) are repeated.
Claim 12
Dependent Claim
30 words
The thin film deposition method as defined in Claim 10 or 11, wherein the pressures being set in steps (iii) and (vii) are less than about 1.5 x 10⁻² Torr.
Claim 13
Dependent Claim
33 words
The thin film deposition method as defined in one if claims 10-12, wherein the temperature of the vacuum side-exposed wall (T wall) being set in steps (v) and (ix) are about 10 °C.
Claim 14
Dependent Claim
35 words
The thin film deposition method as defined in one of claims 10-13, wherein the thin film being deposited on the wafer in steps (ii) through (v) are thin films being deposited by the epitaxial growth.
Claim 15
Dependent Claim
30 words
The thin film deposition method as defined in one of claim 10-14, wherein the thin films being deposited on the wafer in steps (vi) through (x) are polycrystalline thin films.
Claim 16
Dependent Claim
31 words
The thin film deposition method as defined in one of claims 1-15, wherein the thin films being deposited on the wafer in steps (vi) through (x) are thin films containing impurities.
Claim 17
Dependent Claim
43 words
The thin film deposition method as defined in one of claims 10-16, wherein the reactant gas being supplied in step (ii) is Si₂H₆ gas, and wherein the reactant gas being supplied in step (vi) is a mixture of Si₂H₆ gas and B₂H₆ gas.
Claim 18
Dependent Claim
46 words
The thin film deposition method as defined in one of claims 10-17, wherein the reactant gas being suplied in step (ii) is Si₂H₆ gas, and wherein the reactant gas being supplied in step (vi) is a mixture of Si₂H₆ gas and H₂ gas containing B₂H₆ gas.
Claim 19
Dependent Claim
40 words
The thin film deposition method as defined in one of claims 14-18 wherein the reactant gas being supplied in step (ii) is Si₂H₆ gas, and wherein a thin film being deposited on the wafer is an epitaxial Si thin film.
Claim 20
Dependent Claim
44 words
The thin film deposition method as defined in one of claims 15-19, wherein the reactant gas being supplied in step (vi) is a mixture of Si₂H₆ gas and GeH₄, and wherein a thin film being deposited on the wafer is a Ge/Si thin film.
Claim 21
Dependent Claim
55 words
The thin film deposition method as defined in one of claims 10-20, wherein the reactant gas being supplied in step (vi) is a mixture of Si₂H₆ gas and H₂ gas containing B₂H₆ gas, and wherein the thin film being deposited on the wafer is an epitaxial Si thin film containing B atoms as an impurity.
Claim 22
Dependent Claim
29 words
The thin film deposition method as defined in one of claims 11-21, wherein the rate of the reactant as being supplied in step (vi) is varied for each repetition.
Claim 23
Dependent Claim
50 words
The thin film deposition method as defined in Claim 22, wherein the reactant gas being supplied in step (vi) is a mixture of Si₂H₆ gas and H₂ gas containing B₂H₆ gas, and wherein the rate of H₂ gas containing B₂H₆ gas being supplied is increased or decreased for each repetition.
Claim 24
Dependent Claim
32 words
The thin film deposition method as defined in Claim 23, wherein the thin film being deposited on the wafer is an epitaxial Si thin film containing B atoms having a concentration gradient.
Claim 25
Dependent Claim
29 words
The thin film deposition method as defined in one of claims 10-24, wherein the thin film being deposited on the wafer is a thin film having an super-lattice structure.
Claim 26
Dependent Claim
29 words
The thin film deposition method as defined in Claim 25, wherein the super-lattice structure includes a multilayer structure containing an epitaxial Si thin film and a Ge/Si thin film.
Claim 27
Dependent Claim
41 words
The thin film deposition method as defined in one of claims 10-26, wherein the vacuum side-exposed wall is a shroud mounted inside the vacuum vessel or chamber, and wherein the shroud is maintained to a constant temperature by circulating water therethrough.
Claim 28
Dependent Claim
37 words
The thin film deposition method as defined in one of claims 10-27, wherein the pressure being set in step (i) is established during the baking process for the vacuum vessel or chamber while it is being evacuated.
References Cited (Backward Citations)
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