US5120677A
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Method for making a semiconductor device by doping with arsenic, of at least 25 wt. % into a polysilicon layer
Assignee: Lapis Semiconductor Co Ltd
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Filing: 1990-03-20
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Granted: 1992-06-09
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Expires: 2010-03-20
Abstract
Abstract PCT No. PCT/JP90/00372 Sec. 371 Date Nov. 15, 1990 Sec. 102(e) Date Nov. 15, 1990 PCT Filed Mar. 20, 1990 PCT Pub. No. WO90/11618 PCT Pub. Date Oct. 4, 1990.A method for introducing an impurity into a polysilicon formed on an insulating film is described. A silicate glass layer (13) containing As is formed on a polysilicon layer (12) formed on an insulating film (2) and is thermally treated to introduce As into the polysilicon layer (12). The silicate glass layer (13) has a concentration of arsenic of not less than 25 wt. %, calculated as As2O3 and the thermal treatment is effected in an atmosphere of a mixed gas of N2 and O2 with an oxygen partial pressure ratio of 0.05-0.7 at not lower than 1000 DEG C. for not shorter than 60 minutes.
Inventors
- 👤 Hidetoshi Wakamatsu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:48
CPC Classifications
H; H10; H10B; H10B12/00; H10B12/30; H10B12/37; H10P; H10P14/00; H10P14/40; H10P14/412; H10P14/416; H10P95/00; H10P95/90; Y; Y10; Y10S; Y10S148/00; Y10S148/035; Y10S148/133
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
102 words
A method for fabricating a semiconductor device comprising the steps of: forming a polysilicon layer on an insulating film; forming on the polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt %, calculated as As 2 O 3 ; and then introducing arsenic into the polysilicon layer by thermal treatment in an atmosphere of a mixed gas of oxygen and nitrogen with the ratio of the oxygen partial pressure to the total gas pressure being between 0.05/1 and 0.7/1 at a temperature of not lower than 1000° C. for not shorter than 60 minutes.
Claim 2
Independent Claim
102 words
A method for fabricating a semiconductor device comprising the steps of: forming a polysilicon layer on an insulating film; forming on the polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt %, calculated as As 2 O 3 ; and then introducing arsenic into the polysilicon layer by thermal treatment in an atmosphere of a mixed gas of oxygen and nitrogen with the ratio of the oxygen partial pressure to the total gas pressure being between 0.05/1 and 0.7/1 at a temperature of not lower than 1000° C. for not shorter than 60 minutes.
Claim 3
Dependent Claim
21 words
A method for fabricating a semiconductor device according to claim 1, wherein said insulating film is formed on a semiconductor substrate.
Claim 4
Dependent Claim
20 words
A method for fabricating a semiconductor device according to claim 1, wherein said insulating film is a silicon oxide film.
Claim 5
Independent Claim
138 words
A method for fabricating a stacked capacitor comprising the steps of: forming a groove in a semiconductor substrate; forming a first insulating film on inner walls of said groove; forming a polysilicon layer on the first insulating film; forming on the polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt % calculated as As 2 O 3 ; subjecting the polysilicon film to thermal treatment in an atmosphere of a mixed gas of N 2 and O 2 with an oxygen partial pressure ratio of 0.05-0.7 at not lower than 1000° C. for not less than 60 minutes to render the polysilicon film electrically conductive; removing the silicate glass layer; forming a second insulating film on the conductive polysilicon film; and forming an electrode layer on the second insulating film.
Claim 6
Independent Claim
138 words
A method for fabricating a stacked capacitor comprising the steps of: forming a groove in a semiconductor substrate; forming a first insulating film on inner walls of said groove; forming a polysilicon layer on the first insulating film; forming on the polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt % calculated as As 2 O 3 ; subjecting the polysilicon film to thermal treatment in an atmosphere of a mixed gas of N 2 and O 2 with an oxygen partial pressure ratio of 0.05-0.7 at not lower than 1000° C. for not less than 60 minutes to render the polysilicon film electrically conductive; removing the silicate glass layer; forming a second insulating film on the conductive polysilicon film; and forming an electrode layer on the second insulating film.
Claim 7
Dependent Claim
31 words
A method for fabricating a stacked capacitor according to claim 4, wherein after the formation of the first insulating film, part of the groove at a shoulder portion thereof is removed.
Claim 8
Dependent Claim
22 words
A method for fabricating a stacked capacitor according to claim 4, wherein said semiconductor substrate is provided with a field oxide film.
Claim 9
Dependent Claim
25 words
A method for fabricating a stacked capacitor according to claim 5, wherein said groove is formed at an end portion of the field oxide film.
Claim 10
Independent Claim
93 words
A method for fabricating a semiconductor device comprising the steps of: forming on a polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt %, calculated as As 3 O 2 , and introducing arsenic into the polysilicon layer by thermal treatment in an atmosphere of a mixed gas of oxygen and nitrogen with the ratio of the oxygen partial pressure to the total gas pressure being between 0.05/1 and 0.7/1 at a temperature of not lower than 1000° C. for not shorter than 60 minutes.
Claim 11
Independent Claim
93 words
A method for fabricating a semiconductor device comprising the steps of: forming on a polysilicon layer a silicate glass layer wherein a concentration of arsenic is not less than 25 wt %, calculated as As 3 O 2 , and introducing arsenic into the polysilicon layer by thermal treatment in an atmosphere of a mixed gas of oxygen and nitrogen with the ratio of the oxygen partial pressure to the total gas pressure being between 0.05/1 and 0.7/1 at a temperature of not lower than 1000° C. for not shorter than 60 minutes.
Claim 12
Dependent Claim
23 words
A method for fabricating a semiconductor device according to claim 1, further comprising the step of performing said thermal treatment in one step.
Claim 13
Dependent Claim
23 words
A method for fabricating a semiconductor device according to claim 4, further comprising the step of performing said thermal treatment in one step.
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