Patent US4874464A successfully refreshed from Google Patents.
US4874464A
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Process for epitaxial deposition of silicon
Assignee: ASM America Inc
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Filing: 1988-03-14
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Granted: 1989-10-17
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Expires: 2008-03-14
Abstract
Abstract The present invention relates to a high throughput single crystal epitaxial deposition process which achieves increased uniformity, both wafer to wafer and across the wafer surface. There is provided an epitaxial deposition process characterized by low-level cooling periods which minimize temperature changes between deposition cycles and inter-cycle cleaning so that each new wafer is presented with a substantially equivalent deposition environment.
Inventors
- 👤 Dennis L. Goodwin
- 👤 Mark R. Hawkins
- 👤 Wayne L. Johnson
- 👤 Aage Olsen
- 👤 McDonald Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:04
CPC Classifications
C; C30; C30B; C30B29/00; C30B29/02; C30B29/06; C30B25/00; C30B25/02; C30B25/10; Y; Y10; Y10S; Y10S438/00; Y10S438/905
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
141 words
A process for epitaxial deposition of a semiconductor material onto a substrate, comprising the steps of: loading the substrate onto a susceptor in a deposition reactor reaction chamber at an elevated temperature; purging the deposition reactor of ambient gases while simultaneously heating the deposition reactor to a temperature greater than deposition temperature; etching the substrate with an etchant gas to remove impurities from its exposed surface; purging the deposition reactor of said etchant gas while simultaneously reducing the temperature of the deposition reactor to deposition temperature; flowing a gaseous stream of a reactant semiconductor species into the deposition reactor, thereby depositing said reactant semiconductor species onto said exposed surface of said semiconductor wafer; purging the deposition reactor of ambient gases while cooling the deposition reactor to said elevated temperature; and unloading the semiconductor wafer having said reactant semiconductor species deposited thereupon.
Claim 2
Dependent Claim
141 words
A process for epitaxial deposition of a semiconductor material onto a substrate, comprising the steps of: loading the substrate onto a susceptor in a deposition reactor reaction chamber at an elevated temperature; purging the deposition reactor of ambient gases while simultaneously heating the deposition reactor to a temperature greater than deposition temperature; etching the substrate with an etchant gas to remove impurities from its exposed surface; purging the deposition reactor of said etchant gas while simultaneously reducing the temperature of the deposition reactor to deposition temperature; flowing a gaseous stream of a reactant semiconductor species into the deposition reactor, thereby depositing said reactant semiconductor species onto said exposed surface of said semiconductor wafer; purging the deposition reactor of ambient gases while cooling the deposition reactor to said elevated temperature; and unloading the semiconductor wafer having said reactant semiconductor species deposited thereupon.
Claim 3
Dependent Claim
43 words
The process according to claim 1, wherein said step of loading the substrate, further comprises the step of loading the substrate onto a pre-heated susceptor in the deposition reactor at a temperature in the range of about 600° C. to about 1000° C.
Claim 4
Dependent Claim
47 words
The process according to claim 1, wherein said step of purging the deposition reactor of ambient gases while heating the deposition reactor further comprises the step of heating the susceptor and deposition reactor to a temperature in the range of about 1150° C. to about 1200° C.
Claim 5
Dependent Claim
39 words
The process according to claim 1, wherein said step of etching the substrate further comprises the step of flowing HCl doped hydrogen gas across the substrate at a rate of about 60 to about 100 standard liters per minute.
Claim 6
Dependent Claim
32 words
The process according to claim 4, wherein said step of etching the substrate further comprises the step of providing hydrogen gas having about 0.3 to about 1.5 volume percent HCl doped therein.
Claim 7
Dependent Claim
44 words
The process according to claim 1, wherein said step of purging the deposition reactor of said etchant gas further comprises the steps of purging the deposition reactor with hydrogen gas and reducing the temperature of the susceptor and deposition reactor to about 1135° C.
Claim 8
Dependent Claim
40 words
The process according to claim 1, wherein said step of flowing a gaseous stream of a reactant semiconductor species into the deposition reactor further comprises the step of flowing SiHCl 3 into the deposition reactor and across the substrate surface.
Claim 9
Dependent Claim
39 words
The process according to claim 7, wherein said step of flowing SiHCl 3 into the deposition reactor further comprises the step of flowing SiHCl 3 into the deposition reactor at a rate of about 12 to about 20 gm/minute.
Claim 10
Dependent Claim
102 words
The process according to claim 1, further comprising the steps of: sealing the deposition reactor chamber from a wafer handling area of the deposition reactor; flowing an etchant gas into the deposition reactor chamber in a carrier gas while heating the deposition reactor to a temperature greater than deposition temperature; etching said susceptor and said deposition reactor with said etchant gas to remove substantially all reactant semiconductor species deposited thereupon; and purging the deposition reactor of ambient etchant gas while simultaneously cooling the susceptor and deposition reaction chamber to said elevated temperature, thereby preparing the deposition reactor for a subsequent deposition run.
Claim 11
Dependent Claim
39 words
The process accoring to claim 9, wherein said step of flowing an etchant gas reactor further comprises the step of flowing HCl doped hydrogen gas into the deposition reactor at a rate of about 20 standard liters per minute.
Claim 12
Dependent Claim
36 words
The process according to claim 10, wherein said step of etching said susceptor and the deposition reactor further comprises the step of providing hydrogen gas having about 0.3 to about 1.5 volume percent HCl doped therein.
Claim 13
Dependent Claim
57 words
The process according to claim 9, wherein said step of flowing an etchant gas further comprises the steps of etching said susceptor with HCl doped hydrogen gas flowing at about 20 standard liters per minute and, thereafter, increasing the flow of HCl doped hydrogen gas to about 100 standard liters per minute to etch the deposition reactor.
Claim 14
Dependent Claim
228 words
A process for epitaxial deposition of a semiconductor material onto a semiconductor wafer, comprising the steps of: loading the semiconductor wafer onto a susceptor in a deposition reactor at an elevated temperature in the range of 600° C. to about 1000° C.; purging the deposition reactor with hydrogen while simultaneously heating the deposition reactor to a temperature in the range of about 1150° C. to about 1250° C.; etching the semiconductor wafer with HCl doped hydrogen gas to remove impurities from its exposed surface; purging the deposition reactor of said etchant gas while simultaneously reducing the temperature of the deposition reactor to deposition temperature; flowing a gaseous stream of a reactant semiconductor species into the deposition reactor, thereby depositing said reactant semiconductor species onto said exposed surface of said semiconductor wafer; cooling the deposition reactor to said elevated temperature and unloading the semiconductor wafer having said reactant semiconductor species deposited thereupon; purging the deposition reactor with hydrogen while simultaneously heating the deposition reactor to a temperature in the range of about 1150° C. to about 1250° C.; etching said susceptor and said deposition reactor with HCl-doped hydrogen gas to remove substantially all reactant semiconductor species deposited thereupon; and purging the deposition reactor of ambient etchant gas while simultaneously cooling the susceptor and deposition reactor to said elevated temperature, thereby preparing the deposition reactor for a subsequent deposition run.
Claim 15
Dependent Claim
228 words
A process for epitaxial deposition of a semiconductor material onto a semiconductor wafer, comprising the steps of: loading the semiconductor wafer onto a susceptor in a deposition reactor at an elevated temperature in the range of 600° C. to about 1000° C.; purging the deposition reactor with hydrogen while simultaneously heating the deposition reactor to a temperature in the range of about 1150° C. to about 1250° C.; etching the semiconductor wafer with HCl doped hydrogen gas to remove impurities from its exposed surface; purging the deposition reactor of said etchant gas while simultaneously reducing the temperature of the deposition reactor to deposition temperature; flowing a gaseous stream of a reactant semiconductor species into the deposition reactor, thereby depositing said reactant semiconductor species onto said exposed surface of said semiconductor wafer; cooling the deposition reactor to said elevated temperature and unloading the semiconductor wafer having said reactant semiconductor species deposited thereupon; purging the deposition reactor with hydrogen while simultaneously heating the deposition reactor to a temperature in the range of about 1150° C. to about 1250° C.; etching said susceptor and said deposition reactor with HCl-doped hydrogen gas to remove substantially all reactant semiconductor species deposited thereupon; and purging the deposition reactor of ambient etchant gas while simultaneously cooling the susceptor and deposition reactor to said elevated temperature, thereby preparing the deposition reactor for a subsequent deposition run.
Claim 16
Dependent Claim
39 words
The process according to claim 13, wherein said step of etching the substrate further comprises the step of flowing HCl doped hydrogen gas across the substrate at a rate of about 60 to about 100 standard liters per minute.
Claim 17
Dependent Claim
32 words
The process according to claim 14, wherein said step of etching the substrate further comprises the step of providing hydrogen gas having about 0.3 to about 1.5 volume percent HCl doped therein.
Claim 18
Dependent Claim
44 words
The process according to claim 13, wherein said step of purging the deposition reactor of said etchant gas further comprises the steps of purging the deposition reactor with hydrogen gas and reducing the temperature of the susceptor and deposition reactor to about 1135° C.
Claim 19
Dependent Claim
40 words
The process according to claim 13, wherein said step of flowing a gaseous stream of a reactant semiconductor species into the deposition reactor further comprises the step of flowing SiHCl 3 into the deposition reactor and across the substrate surface.
Claim 20
Dependent Claim
39 words
The process according to claim 17, wherein said step of flowing SiHCl 3 into the deposition reactor further comprises the step of flowing SiHCl 3 into the deposition reactor at a rate of about 12 to about 20 gm/minute.
Claim 21
Dependent Claim
41 words
The process according to claim 13, wherein said step of etching said susceptor and said deposition reactor further comprises the step of flowing HCl doped hydrogen gas into the deposition reactor at a rate of about 20 standard liters per minute.
Claim 22
Dependent Claim
35 words
The process according to claim 19, wherein said step of etching said susceptor and deposition reactor further comprises the step of providing hydrogen gas having about 0.3 to about 1.5 volume percent HCl doped therein.
Claim 23
Dependent Claim
60 words
The process according to claim 13, wherein said step of etching said susceptor and said deposition reactor further comprises the steps of etching said receptor with HCl doped hydrogen gas flowing at about 20 standard liters per minute and, thereafter, increasing the flow of HCl doped hydrogen gas to about 100 standard liters per minute to etch the deposition reactor.
References Cited (Backward Citations)
US3473978A
Cited
US4138306A
Cited
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