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US4806201A Expired / Lapsed US ⏱️ 0.0 years remaining

Use of sidewall oxide to reduce filaments

Assignee: Texas Instruments Inc
•
Filing: 1988-03-21
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Granted: 1989-02-21
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Expires: 2008-03-21
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Abstract

Abstract The disclosure relates to a method for reducing filament formation over the BN+ oxide in semiconductor devices wherein a sidewall oxide is formed on the side walls of the first polysilicon layer prior to subsequent formation of the intermediate insulating layer, formation of a second polysilicon layer and subsequent anisotropic etch to provide for removal of all polysilicon over the field oxide.

Inventors

  • 👤 Allan T. Mitchell
  • 👤 Howard L. Tigelaar
  • 👤 Shaym G. Garg
  • 👤 Kalipatnam V. Rao

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 09:00
CPC Classifications
H; H10; H10P; H10P76/00; H10P76/40; H10P76/408; H10P76/4085; H10D; H10D64/00; H10D64/01; H10D64/031; H10D64/035

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 64 words
A method for fabricating an integrated circuit at a surface of a semiconductor body, comprising: forming a first electrode at said surface; forming sidewall dielectric structures adjacent the edges of said first electrode; forming an interlevel dielectric layer over said first electrode and said sidewall dielectric structures; and forming a second electrode over said dielectric layer and overlying a portion of said first electrode.
Claim 2
Independent Claim 64 words
A method for fabricating an integrated circuit at a surface of a semiconductor body, comprising: forming a first electrode at said surface; forming sidewall dielectric structures adjacent the edges of said first electrode; forming an interlevel dielectric layer over said first electrode and said sidewall dielectric structures; and forming a second electrode over said dielectric layer and overlying a portion of said first electrode.
Claim 3
Dependent Claim 21 words
The method of claim 1, wherein said step of forming said interlevel dielectric layer comprises: depositing a layer of silicon oxide.
Claim 4
Dependent Claim 28 words
The method of claim 2, wherein said step of forming said interlevel dielectric layer further comprises: depositing a layer of silicon nitride over said layer of silicon oxide.
Claim 5
Dependent Claim 26 words
The method of claim 1, wherein said step of forming a second electrode comprises: depositing a polysilicon layer; and removing selected portions of said polysilicon layer.
Claim 6
Dependent Claim 35 words
The method of claim 4, wherein said step of removing selected portions of said polysilicon layer comprises: providing masking material over the portion of said polysilicon layer; etching the unmasked portion of said polysilicon layer.
Claim 7
Dependent Claim 26 words
The method of claim 5, wherein said etching step also etches a portion of said interlevel dielectric layer underlying the unmasked portion of said polysilicon layer.
Claim 8
Dependent Claim 33 words
The method of claim 1, further comprising: forming a buried doped region; and forming an oxide layer overlying said buried doped region; wherein said first electrode overlays a portion of said oxide layer.
Claim 9
Dependent Claim 77 words
The method of claim 1, further comprising: forming first and second buried doped regions; forming a first and a second oxide structure overlying said first and said second buried doped regions, respectively; and forming a gate dielectric over a portion of said surface lying between said first and second oxide structures; wherein said first electrode overlies said gate dielectric and extends from an edge of said first oxide structure to an edge of said second oxide structure.
Claim 10
Dependent Claim 13 words
The method of claim 8, wherein said first electrode is formed of polysilicon.
Claim 11
Dependent Claim 21 words
The method of claim 9, wherein said step of forming said interlevel dielectric layer comprises: depositing a layer of silicon oxide.
Claim 12
Dependent Claim 28 words
The method of claim 10, wherein said step of forming said interlevel dielectric layer further comprises: depositing a layer of silicon nitride over said layer of silicon oxide.
Claim 13
Dependent Claim 26 words
The method of claim 9, wherein said step of forming a second electrode comprises: depositing a polysilicon layer; and removing selected portions of said polysilicon layer.
Claim 14
Dependent Claim 35 words
The method of claim 12, wherein said step of removing selected portions of said polysilicon layer comprises: providing masking material over the portion of said polysilicon layer; etching the unmasked portion of said polysilicon layer.
Claim 15
Dependent Claim 26 words
The method of claim 13, wherein said etching step also etches a portion of said interlevel dielectric layer underlying the unmasked portion of said polysilicon layer.

References Cited (Backward Citations)

US4566175A Cited
US4628588A Cited
US4713142A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-02-21 1992-08-22 1993-02-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-02-21 1996-08-22 1997-02-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-02-21 2000-08-22 2001-02-21 $7700.00 Window Closed / Lapsed

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