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US4579621A
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Selective epitaxial growth method
Assignee: Mitsubishi Electric Corp
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Filing: 1984-06-25
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Granted: 1986-04-01
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Expires: 2004-06-25
Abstract
Abstract Disclosed herein is a selective epitaxial growth method for forming an opening, utilizing anisotropic dry etching, in a silicon oxide film formed on a silicon substrate and epitaxially growing a silicon layer selectively in the opening. The anisotropic dry etching is performed employing a mixed gas of carbon tetrafluoride and hydrogen, and the wall surface of the opening is perpendicular to the major surface of the silicon substrate. The epitaxial growth is achieved under a temperature of 900° to 1100° C. utilizing a mixed gas of a low pressure under 100 Torr. containing dichlorosilane as a silicon source and hydrogen as a carrier gas. A silicon layer thus obtained contains substantially no lattice defects such as a stacked fault.
Inventors
- 👤 Shiro Hine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 12:55
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; C; C30; C30B; C30B25/00; C30B25/02; C30B25/04; H10P14/00; H10P14/20; H10P14/24; H10P14/27; H10P14/271; H10P14/29; H10P14/2901; H10P14/2902; H10P14/2905; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3438; H10P14/3441; H10P14/3442; H10P14/3444
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
180 words
A selective epitaxial growth method of epitaxially growing a semiconductor layer selectively on the major surface of a semiconductor substrate, said selective epitaxial growth method comprising the steps of: preparing a semiconductor substrate; forming an insulating film on the major surface of said semiconductor substrate; forming a resist film having a predeterminied pattern on said insulating film; utilizing said resist film as a mask for performing anisotropic dry etching with respect to said insulating film, said anisotropic dry etching being performed by utilizing a mixed gas of carbon tetrafluoride and hydrogen as an etchant to thereby form an opening in and corresponding to said pattern in said insulating film, said opening having a peripheral vertical edge extending generally perpendicular to said major surface of said semiconductor substrate; and exposing said semiconductor substrate to a low-pressure gas containing a semiconductor element, thereby expitaxially growing a semiconductor layer containing said semiconductor element selectively in said opening, said epitaxially grown semiconductor layer being generally free of lattice defects along its periphery as a result of forming said opening with said peripheral vertical edge.
Claim 2
Dependent Claim
180 words
A selective epitaxial growth method of epitaxially growing a semiconductor layer selectively on the major surface of a semiconductor substrate, said selective epitaxial growth method comprising the steps of: preparing a semiconductor substrate; forming an insulating film on the major surface of said semiconductor substrate; forming a resist film having a predeterminied pattern on said insulating film; utilizing said resist film as a mask for performing anisotropic dry etching with respect to said insulating film, said anisotropic dry etching being performed by utilizing a mixed gas of carbon tetrafluoride and hydrogen as an etchant to thereby form an opening in and corresponding to said pattern in said insulating film, said opening having a peripheral vertical edge extending generally perpendicular to said major surface of said semiconductor substrate; and exposing said semiconductor substrate to a low-pressure gas containing a semiconductor element, thereby expitaxially growing a semiconductor layer containing said semiconductor element selectively in said opening, said epitaxially grown semiconductor layer being generally free of lattice defects along its periphery as a result of forming said opening with said peripheral vertical edge.
Claim 3
Dependent Claim
32 words
A selective epitaxial growth method in accordance with claim 1, wherein said semiconductor substrate is a silicon substrate having an active region therein and said insulating film is a silicon oxide film.
Claim 4
Dependent Claim
25 words
A selective epitaxial growth method in accordance with claim 2, wherein said anisotropic dry etching is performed in a parallel-plane type anisotropic dry etcing device.
Claim 5
Dependent Claim
36 words
A selective epitaxial growth method in accordance with claim 3, wherein said semiconductor element is silicon and said low-pressure gas is a mixed gas containing dichlorosilane as a silicon source and hydrogen as a carrier gas.
Claim 6
Dependent Claim
20 words
A selective epitaxial growth method in accordance with claim 4, wherein said low-pressure gas has a pressure under 100 Torr.
Claim 7
Dependent Claim
25 words
A selective epitaxial growth method in accordance with claim 5, wherein said selective epitaxial growth is achieved under a temperature of 900° to 1100° C.
Claim 8
Dependent Claim
56 words
A selective epitaxial growth method in accordance with claim 6, wherein said semiconductor substrate is of a first conductive type, and the conductive type of said semiconductor layer is determined to be either said first conductive type or a second conductive type depending on the conductive type of an impurity gas mixed into said silicon source.
Claim 9
Dependent Claim
41 words
The selective epitaxial growth method of claim 1, wherein said anisotropic etching is performed and exposure to said low-pressure gas occurs at predetermined temperatures and predetermined pressures such that lattice defects, if any, have a length of less than 5000 Å.
References Cited (Backward Citations)
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