US5637528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Semiconductor device manufacturing method including dry oxidation
Assignee: Fujitsu Ltd
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Filing: 1996-08-22
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Granted: 1997-06-10
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Expires: 2016-08-22
Abstract
Abstract A method of manufacturing a semiconductor device including the steps of: (a) forming a mask layer of a desired pattern on a silicon substrate surface or on an SiO 2 strain absorbing layer formed on the silicon substrate surface; (b) selectively oxidizing the silicon substrate in a dry oxygen atmosphere by using the mask layer as an oxidation mask; and (c) selectively oxidizing the silicon substrate in an atmosphere of dry oxygen mixed with gas containing halogen element, wherein a field oxide film having a thickness of 100 nm or more is formed. The first and second oxidizing steps (b) and (c) are preferably performed at temperatures between 950° C. and 1200° C. A field oxide film with a short bird's beak can be formed while maintaining a relatively high oxidation speed and preventing generation of a white ribbon.
Inventors
- 👤 Masaaki Higashitani
- 👤 Kenichi Hikazutani
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:56
CPC Classifications
H; H10; H10W; H10W10/00; H10W10/01; H10W10/011; H10W10/012; H10W10/10; H10W10/13; H10P; H10P14/00; H10P14/60; H10P14/63; H10P14/6302; H10P14/6304; H10P14/6306; H10P14/6308; H10P14/6309; H10P14/6322
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
135 words
A method of manufacturing a semiconductor device comprising the steps of: (a) forming a mask layer of a desired pattern on a silicon substrate surface or on an SiO 2 strain absorbing layer formed on said silicon substrate surface; (b) selectively oxidizing said silicon substrate in a dry oxygen atmosphere without adding halogen element by using said mask layer as an oxidation mask; and (c) selectively oxidizing said silicon substrate in an atmosphere of dry oxygen mixed with gas containing halogen element, wherein each of said first and second oxidizing steps (b) and (c) includes oxidation at a temperature between about 1050° C. and 1200° C., said gas containing halogen element has a concentration of 1 V % or less, and a field oxide film having a thickness of 100 nm or more is formed.
Claim 2
Independent Claim
135 words
A method of manufacturing a semiconductor device comprising the steps of: (a) forming a mask layer of a desired pattern on a silicon substrate surface or on an SiO 2 strain absorbing layer formed on said silicon substrate surface; (b) selectively oxidizing said silicon substrate in a dry oxygen atmosphere without adding halogen element by using said mask layer as an oxidation mask; and (c) selectively oxidizing said silicon substrate in an atmosphere of dry oxygen mixed with gas containing halogen element, wherein each of said first and second oxidizing steps (b) and (c) includes oxidation at a temperature between about 1050° C. and 1200° C., said gas containing halogen element has a concentration of 1 V % or less, and a field oxide film having a thickness of 100 nm or more is formed.
Claim 3
Dependent Claim
40 words
A method according to claim 1, wherein said second oxidizing step (c) is performed continuously after the end of said first oxidizing step (b), in an oxidizing atmosphere of said first oxidizing step (b) added with gas containing halogen element.
Claim 4
Dependent Claim
32 words
A method according to claim 1, wherein said gas containing halogen element is HCl, C 2 H 3 Cl 3 , C 2 H 2 Cl 2 , or Cl 2 gas.
Claim 5
Dependent Claim
52 words
A method according to claim 1, wherein said first oxidizing step (b) includes a front stage to be done at a first temperature and a back stage to be done at a second temperature higher than said first temperature, said first temperature being in a range from 950° C. to 1200° C.
Claim 6
Dependent Claim
32 words
A method according to claim 4, wherein said first oxidizing step (b) includes a middle stage for raising a temperature in an atmosphere containing inert gas, between said front and back stages.
Claim 7
Dependent Claim
38 words
A method according to claim 5, wherein said first oxidizing step (b) includes a stabilizing stage for reaching a steady state by maintaining said second temperature in an inert gas atmosphere, between said middle stage and back stage.
Claim 8
Dependent Claim
22 words
A method according to claim 4, wherein said second temperature is higher by about 100° C. or more than said first temperature.
Claim 9
Independent Claim
82 words
A method of manufacturing a semiconductor device comprising the steps of: (a) oxidizing a silicon substrate in a dry oxygen atmosphere without adding halogen element; and (b) oxidizing said silicon substrate in an atmosphere of dry oxygen added with gas containing halogen element, wherein each of said first and second oxidizing steps (a) and (b) includes oxidation at a temperature between about 1050° C. and 1200° C., and said gas containing halogen element has a concentration of 1 V % or less.
Claim 10
Independent Claim
82 words
A method of manufacturing a semiconductor device comprising the steps of: (a) oxidizing a silicon substrate in a dry oxygen atmosphere without adding halogen element; and (b) oxidizing said silicon substrate in an atmosphere of dry oxygen added with gas containing halogen element, wherein each of said first and second oxidizing steps (a) and (b) includes oxidation at a temperature between about 1050° C. and 1200° C., and said gas containing halogen element has a concentration of 1 V % or less.
Claim 11
Dependent Claim
44 words
A method according to claim 8, wherein said second oxidizing step (b) is performed continuously after the end of said first oxidizing step (a), at the same temperature, in an oxidizing atmosphere of said first oxidizing step (a) added with gas containing halogen element.
Claim 12
Dependent Claim
32 words
A method according to claim 8, wherein said gas containing halogen element is HCl, C 2 H 3 Cl 3 , C 2 H 2 Cl 2 , or Cl 2 gas.
Claim 13
Dependent Claim
39 words
A method according to claim 8, wherein said first oxidizing step (a) includes a front stage to be done at a first temperature and a back stage to be done at a second temperature higher than said first temperature.
Claim 14
Dependent Claim
32 words
A method according to claim 11, wherein said first oxidizing step (a) includes a middle stage for raising a temperature in an atmosphere containing inert gas, between said front and back stages.
Claim 15
Dependent Claim
38 words
A method according to claim 12, wherein said first oxidizing step (a) includes a stabilizing stage for reaching a steady state by maintaining said second temperature in an inert gas atmosphere, between said middle stage and back stage.
Claim 16
Dependent Claim
22 words
A method according to claim 11, wherein said second temperature is higher by about 100° C. or more than said first temperature.
Claim 17
Dependent Claim
17 words
A method according to claim 1, wherein said temperature is between about 1100° C. and 1200° C.
Claim 18
Dependent Claim
15 words
A method according to claim 1, wherein said oxidations are performed at the same temperature.
Claim 19
Dependent Claim
20 words
A method according to claim 9, wherein said same temperature is in a range between 1100° C. and 1200° C.
References Cited (Backward Citations)
JPH02260638A
Cited
US5151381A
Cited
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