Patent DE703364C successfully refreshed from Google Patents.
← Back to Patent Explorer
US6436746B1 Expired / Lapsed US ⏱️ 0.0 years remaining

Transistor having an improved gate structure and method of construction

Assignee: Texas Instruments Inc
•
Filing: 1999-01-05
•
Granted: 2002-08-20
•
Expires: 2019-01-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A method of fabricating an improved gate structure that may be used in a transistor. A primary insulation layer (22) may be formed adjacent a substrate (12). A disposable gate (24) may be formed adjacent the primary insulation layer (22). An isolation dielectric layer (26) may be formed adjacent the primary insulation layer (22). The disposable gate (24) may be removed to expose a portion of the primary insulation layer (22). The exposed portion of the primary insulation layer (22) may be removed to expose a portion of the substrate (12). The primary insulation layer (22) may be selectively removable relative to the isolation dielectric layer (26). A gate insulator (30) may be formed on the exposed portion of the substrate (12). A gate (32) may be formed adjacent the gate insulator (30).

Inventors

  • 👤 Amitava Chatterjee
  • 👤 Wei William Lee
  • 👤 Greg A. Hames
  • 👤 Qizhi He
  • 👤 Maureen Hanratty
  • 👤 Iqbal Ali

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 01:33
CPC Classifications
H; H10; H10D; H10D64/00; H10D64/01; H10D64/017; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10D64/013; H10D64/01302; H10D64/01304; H10D64/01324; H10D64/20; H10D64/27; H10D64/311; H10D64/411; H10D64/511; H10D64/517; H10D64/518; H10W; H10W20/00; H10W20/01; H10W20/031; H10W20/0698

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 151 words
A method of forming a gate structure, comprising the steps of: forming a primary insulation layer adjacent a semiconductor substrate, the primary insulation layer comprising a first material; forming a disposable gate having sidewalls on the primary insulation layer; forming an isolation dielectric layer on and in contact with the primary insulation layer and said sidewalls of said disposable gate, the isolation dielectric layer comprising a second material, the second material different from the first material and selectively etchable relative to said first material; removing the disposable gate to expose a portion of the primary insulation layer; removing the exposed portion of the primary insulation layer to expose a portion of the substrate using an etch process selective to the first material relative to the second material; forming a gate insulator on the exposed portion of the substrate; and forming a gate on the gate insulator and isolated from said substrate.
Claim 2
Independent Claim 151 words
A method of forming a gate structure, comprising the steps of: forming a primary insulation layer adjacent a semiconductor substrate, the primary insulation layer comprising a first material; forming a disposable gate having sidewalls on the primary insulation layer; forming an isolation dielectric layer on and in contact with the primary insulation layer and said sidewalls of said disposable gate, the isolation dielectric layer comprising a second material, the second material different from the first material and selectively etchable relative to said first material; removing the disposable gate to expose a portion of the primary insulation layer; removing the exposed portion of the primary insulation layer to expose a portion of the substrate using an etch process selective to the first material relative to the second material; forming a gate insulator on the exposed portion of the substrate; and forming a gate on the gate insulator and isolated from said substrate.
Claim 3
Dependent Claim 22 words
The method of claim 1 , further comprising the step of creating source-drain regions in an upper surface of the semiconductor substrate.
Claim 4
Dependent Claim 41 words
The method of claim 1 , wherein the step of forming a disposable gate on the primary insulation layer comprises: forming a gate layer above the primary insulation layer; and patterning and etching the gate layer to form a disposable gate.
Claim 5
Dependent Claim 60 words
The method of claim 1 , wherein the step of forming an isolation dielectric layer over the primary insulation layer comprises: forming a silicon oxynitride layer, said silicon oxynitride layer having a depth which is greater than a depth of the disposable gate; and removing an upper portion of the silicon oxynitride layer which lies higher than the disposable gate.
Claim 6
Dependent Claim 45 words
The method of claim 4 , wherein the disposable gate is made of a nitride material and wherein the step of removing the disposable gate comprises the step of etching the disposable gate with hot phosphoric wet etching compound to selectively remove the disposable gate.
Claim 7
Dependent Claim 43 words
The method of claim 4 , wherein the step of removing the exposed portion of the primary insulation layer comprises the step of etching the exposed portion of the primary insulation layer with a wet etching compound selective to said primary insulation layer.
Claim 8
Dependent Claim 27 words
The method of claim 1 , further comprising the step of thermally treating the disposable gate prior to removing the exposed portion of the primary insulation layer.
Claim 9
Dependent Claim 60 words
The method of claim 1 , wherein the step of removing the exposed portion of the primary insulation layer to expose a portion of the substrate comprises the step of removing the, exposed portion of the primary insulation layer at a removal rate of at least 10 times faster than a rate at which the isolation dielectric layer is removed.
Claim 10
Independent Claim 180 words
A method of fabricating a semiconductor component, comprising the steps of: forming a primary insulation layer adjacent a semiconductor substrate; forming a disposable gate having sidewalls and disposed on the primary insulation layer; forming a silicon oxynitride layer on and in contact with the primary insulation layer and said sidewalls of said disposable gate, said silicon oxynitride layer having a depth toward said primary insulation layer which is greater than a depth of the disposable gate and extending to a height above said disposable gate, the disposable gate and primary insulation layer each being selectively removable relative to the silicon oxynitride layer; removing an upper portion of the silicon oxynitride layer which lies higher than the disposable gate, such that at least a portion of the disposable gate is exposed; removing the disposable gate to expose a portion of the primary insulation layer; removing the exposed portion of the primary insulation layer to expose a portion of the semiconductor substrate; forming a gate insulator on the exposed portion of the semiconductor substrate; and forming a gate on the gate insulator.
Claim 11
Independent Claim 180 words
A method of fabricating a semiconductor component, comprising the steps of: forming a primary insulation layer adjacent a semiconductor substrate; forming a disposable gate having sidewalls and disposed on the primary insulation layer; forming a silicon oxynitride layer on and in contact with the primary insulation layer and said sidewalls of said disposable gate, said silicon oxynitride layer having a depth toward said primary insulation layer which is greater than a depth of the disposable gate and extending to a height above said disposable gate, the disposable gate and primary insulation layer each being selectively removable relative to the silicon oxynitride layer; removing an upper portion of the silicon oxynitride layer which lies higher than the disposable gate, such that at least a portion of the disposable gate is exposed; removing the disposable gate to expose a portion of the primary insulation layer; removing the exposed portion of the primary insulation layer to expose a portion of the semiconductor substrate; forming a gate insulator on the exposed portion of the semiconductor substrate; and forming a gate on the gate insulator.
Claim 12
Dependent Claim 25 words
The method of claim 9 , wherein the step of forming a silicon oxynitride layer comprises the step of forming a layer of silicon-rich oxynitride.
Claim 13
Dependent Claim 27 words
The method of claim 9 , further comprising the step of thermally treating the disposable gate prior to removing the exposed portion of the primary insulation layer.
Claim 14
Dependent Claim 56 words
The method of claim 9 , wherein the primary insulation layer is made of an oxide and wherein the step of removing the exposed portion of the primary insulation layer comprises the step of etching the exposed portion of the primary insulation layer with hydrofluoric acid to remove the exposed portion of the primary insulation layer.
Claim 15
Dependent Claim 59 words
The method of claim 10 , wherein the step of removing the exposed portion of the primary insulation layer to expose a portion of the semiconductor substrate comprises the step of removing the exposed portion of the primary insulation layer at a removal rate of at least 10 times faster than a removal rate of the silicon-rich oxynitride layer.

References Cited (Backward Citations)

US5994179A Cited
US6063675A Cited
US6063677A Cited
US5937302A Cited
US6251763B1 Cited
US5960270A Cited
US5856225A Cited
US5976924A Cited
US5998285A Cited
US6210999B1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2005-08-19 2006-02-18 2006-08-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2009-08-19 2010-02-18 2010-08-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2013-08-19 2014-02-18 2014-08-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag