US4877753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
In situ doped polysilicon using tertiary butyl phosphine
Assignee: Texas Instruments Inc
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Filing: 1988-03-01
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Granted: 1989-10-31
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Expires: 2008-03-01
Abstract
Abstract The disclosure relates to a method of forming in situ phosphorous doped polysilicon wherein a surface upon which phosphorous doped polysilicon is to be deposited is placed in a vacuum furnace and, after low pressure HCl cleaning of the surface and furnace, a predetermined ratio of silane and a gaseous phosphorous containing compound taken from the class consisting of phosphorous trichloride, tertiary butyl phosphine, isobutyl phosphine, trimethyl phosphate and tetramethyl phosphate are simultaneously passed through the furnace at predetermined pressure and temperature to provide a uniformly phosphorous doped layer of polysilicon on the surface.
Inventors
- 👤 Dean W. Freeman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:50
CPC Classifications
C; C23; C23C; C23C16/00; C23C16/22; C23C16/24; H; H10; H10P; H10P14/00; H10P14/20; H10P14/24; H10P14/34; H10P14/3402; H10P14/3404; H10P14/3411; H10P14/3438; H10P14/3441; H10P14/3442; Y; Y10; Y10S; Y10S148/00; Y10S148/04; Y10S148/122
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
92 words
A method of forming a layer of phosphorous doped polysilicon, comprising the steps of: (a) providing a furnace having a surface therein for deposition of phosphorous doped polysilicon thereon, (b) evacuating said furnace to a pressure in the range of from about 100 to about 1000 milliTorr., (c) heating said furnace to a temperature of from about 610 to about 700 degrees C., and (d) simultaneously entering a predetermined ratio of silane and gaseous tertiary butyl phosphine into said furnace to form a layer of uniformly phosphorous doped polysilicon on said surface.
Claim 2
Independent Claim
92 words
A method of forming a layer of phosphorous doped polysilicon, comprising the steps of: (a) providing a furnace having a surface therein for deposition of phosphorous doped polysilicon thereon, (b) evacuating said furnace to a pressure in the range of from about 100 to about 1000 milliTorr., (c) heating said furnace to a temperature of from about 610 to about 700 degrees C., and (d) simultaneously entering a predetermined ratio of silane and gaseous tertiary butyl phosphine into said furnace to form a layer of uniformly phosphorous doped polysilicon on said surface.
Claim 3
Dependent Claim
32 words
The method of claim 1 wherein said furnace and said surface are cleaned in an HC1 atmosphere at a pressure of from about 10 to about 20 milliTorr. prior to step (b).
Claim 4
Dependent Claim
37 words
The method of claim 1 wherein the flow rate of said tertiary butyl phosphine is from about 1 to about 10 sccm and the flow rate of said silane is from about 50 to about 100 sccm.
Claim 5
Dependent Claim
37 words
The method of claim 2 wherein the flow rate of said tertiary butyl phosphine is from about 1 to about 10 sccm and the flow rate of said silane is from about 50 to about 100 sccm.
Claim 6
Dependent Claim
22 words
The method of claim 1 wherein said surface is disposed in said furnace substantially normal to the direction of atmosphere flow therein.
Claim 7
Dependent Claim
22 words
The method of claim 2 wherein said surface is disposed in said furnace substantially normal to the direction of atmosphere flow therein.
Claim 8
Dependent Claim
22 words
The method of claim 3 wherein said surface is disposed in said furnace substantially normal to the direction of atmosphere flow therein.
Claim 9
Dependent Claim
22 words
The method of claim 4 wherein said surface is disposed in said furnace substantially normal to the direction of atmosphere flow therein.
Claim 10
Dependent Claim
21 words
The method of claim 1 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 11
Dependent Claim
21 words
The method of claim 2 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 12
Dependent Claim
21 words
The method of claim 3 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 13
Dependent Claim
21 words
The method of claim 4 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 14
Dependent Claim
21 words
The method of claim 5 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 15
Dependent Claim
21 words
The method of claim 6 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 16
Dependent Claim
21 words
The method of claim 7 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
Claim 17
Dependent Claim
21 words
The method of claim 8 wherein said tertiary butyl phosphine is passed through a bubbler prior to entry into said furnace.
References Cited (Backward Citations)
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