Patent US2217839A successfully refreshed from Google Patents.
Patent US4889829A successfully refreshed from Google Patents.
US4889829A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing a semiconductor device having a silicon-on-insulator structure
Assignee: Fujitsu Ltd
•
Filing: 1989-01-17
•
Granted: 1989-12-26
•
Expires: 2009-01-17
Abstract
Abstract A method for producing a semiconductor device having a silicon-on-insulator structure, includes the steps of depositing a first insulation film on a silicon substrate by a chemical vapor deposition process, patterning said first insulation film so as to be left in a silicon-on-insulator (SOI) element region, a portion of said silicon substrate having no first insulation film thereon being served as a bulk element region, depositing a polysilicon layer on an entire surface of said silicon substrate, patterning said polysilicon layer so as to be left on said patterned first insulation film, a patterned polysilicon layer being served as an active region, and simultaneously forming second and third insulation films for use in element insulation in said silicon substrate and said patterned polysilicon layer, respectively, by a local-oxidation-of-silicon (LOCOS) process, so that said bulk element region in surrounded by said second insulation film, and said SOI element region is surrounded by said third insulation film.
Inventors
- 👤 Shinichi Kawai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 00:47
CPC Classifications
H; H10; H10D; H10D87/00; H10D84/00; H10D84/01; H10D84/02; H10D84/03; H10D84/038; H10D88/00; H10D88/01; Y; Y10; Y10S; Y10S438/00; Y10S438/967
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
156 words
A method for producing a semiconductor device having a silicon-on-insulator structure, comprising the steps of: depositing a first insulation film on a silicon substrate by a chemical vapor deposition process; patterning said first insulation film so as to be left in a silicon-on-insulator (SOI) element region, a portion of said silicon substrate having no first insulation film thereon serving as a bulk element region; depositing a polysilicon layer on the entire surface of said silicon substrate; patterning said polysilicon layer so as to be left on said patterned first insulation film, a portion of said patterned polysilicon layer serving as an active region; and simultaneously forming second and third insulation films for use in element insulation in said silicon substrate and said patterned polysilicon layer, respectively, by a local-oxidation-of-silicon (LOCOS) process, so that said bulk element region is surrounded by said second insulation film, and said SOI element region is surrounded by said third insulation film.
Claim 2
Independent Claim
156 words
A method for producing a semiconductor device having a silicon-on-insulator structure, comprising the steps of: depositing a first insulation film on a silicon substrate by a chemical vapor deposition process; patterning said first insulation film so as to be left in a silicon-on-insulator (SOI) element region, a portion of said silicon substrate having no first insulation film thereon serving as a bulk element region; depositing a polysilicon layer on the entire surface of said silicon substrate; patterning said polysilicon layer so as to be left on said patterned first insulation film, a portion of said patterned polysilicon layer serving as an active region; and simultaneously forming second and third insulation films for use in element insulation in said silicon substrate and said patterned polysilicon layer, respectively, by a local-oxidation-of-silicon (LOCOS) process, so that said bulk element region is surrounded by said second insulation film, and said SOI element region is surrounded by said third insulation film.
Claim 3
Dependent Claim
30 words
A method as claimed in claim 1, wherein said silicon substrate comprises a thermal oxidation film formed thereon, and said first insulation film is formed on said thermal oxidation film.
Claim 4
Dependent Claim
42 words
A method as claimed in claim 1, further comprising a step of forming a thermal oxidation film on the portion of said silicon substrate having no first insulation film thereon, and then the step of depositing the polysilicon layer is carried out.
Claim 5
Dependent Claim
30 words
A method as claimed in claim 1, further comprising a step of forming a sidewall film in a stepped portion between said bulk element region and said SOI element region.
Claim 6
Dependent Claim
17 words
A method as claimed in claim 1, further comprising a step of recrystallizing said patterned polysilicon layer.
Claim 7
Dependent Claim
14 words
A method as claimed in claim 1, wherein said polysilicon layer comprises impurity-doped polysilicon.
References Cited (Backward Citations)
US4217153A
Cited
JPS54990A
Cited
US4221044A
Cited
US4221045A
Cited
JPS5710248A
Cited
JPS60245211A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-12-25 | 1993-06-26 | 1993-12-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-12-25 | 1997-06-26 | 1997-12-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-12-25 | 2001-06-26 | 2001-12-26 | $7700.00 | Window Closed / Lapsed |