US5169491A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of etching SiO2 dielectric layers using chemical mechanical polishing techniques
Assignee: Micron Technology Inc
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Filing: 1991-07-29
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Granted: 1992-12-08
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Expires: 2011-07-29
Abstract
Abstract A method of planarizing SiO 2 containing dielectric in semiconductor wafer processing comprising: a) providing a layer of undoped SiO 2 atop a wafer; b) depositing a layer of borophosphosilicate glass atop the layer of undoped SiO 2 ; and c) chemical mechanical polishing the borophosphosilicate glass layer selectively relative to the underlying layer of undoped SiO 2 layer and using the layer of undoped SiO 2 as an effective chemical mechanical polishing end-point etch stop to prevent further etching of the borophosphosilicate glass and produce a substantially planar upper wafer surface of dielectric.
Inventors
- 👤 Trung T. Doan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 16:15
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/06; H10P95/062; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/092
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
A method of planarizing SiO 2 containing dielectric in semiconductor wafer processing comprising the following steps: providing a layer of undoped SiO 2 atop a wafer; depositing a layer of borophosphosilicate glass atop the layer of undoped SiO 2 ; chemical mechanical polishing the borophosphosilicate glass layer using a slurry composition which provides significant selectivity to the underlying layer of undoped SiO 2 and using the layer of undoped SiO 2 as an effective chemical mechanical polishing end-point etch stop to prevent further etching of the borophosphosilicate glass and produce a substantially planar upper wafer surface of dielectric, the slurry composition having a pH from about 7 to about 12 and having a solids concentration of from about 1% to 20% by weight.
Claim 2
Independent Claim
123 words
A method of planarizing SiO 2 containing dielectric in semiconductor wafer processing comprising the following steps: providing a layer of undoped SiO 2 atop a wafer; depositing a layer of borophosphosilicate glass atop the layer of undoped SiO 2 ; chemical mechanical polishing the borophosphosilicate glass layer using a slurry composition which provides significant selectivity to the underlying layer of undoped SiO 2 and using the layer of undoped SiO 2 as an effective chemical mechanical polishing end-point etch stop to prevent further etching of the borophosphosilicate glass and produce a substantially planar upper wafer surface of dielectric, the slurry composition having a pH from about 7 to about 12 and having a solids concentration of from about 1% to 20% by weight.
Claim 3
Dependent Claim
50 words
The method of planarizing SiO 2 containing dielectric of claim 1 wherein the slurry has a solution component and a solids component, the solution component comprising KOH and water, the solids component comprising SiO 2 particles having an average maximum diameter of from about 100 Angstroms to about 500 Angstroms.
Claim 4
Dependent Claim
27 words
The method of planarizing SiO 2 containing dielectric of claim 1 comprising providing the layer of undoped SiO 2 to a thickness of at least 2000 Angstroms.
Claim 5
Dependent Claim
24 words
The method of planarizing SiO 2 containing dielectric of claim 1 comprising depositing the layer of undoped SiO 2 by decomposition of tetraethyl orthosilicate.
Claim 6
Dependent Claim
32 words
The method of planarizing SiO 2 containing dielectric of claim 1 comprising depositing the layer of undoped SiO 2 by decomposition of tetraethyl orthosilicate to a thickness of at least 2000 Angstroms.
Claim 7
Dependent Claim
66 words
The method of planarizing SiO 2 containing dielectric of claim 1 comprising: providing the layer of undoped SiO 2 to a thickness of at least 2000 Angstroms; and the slurry has a solution component and a solids component, the solution component comprising KOH and water, the solids component comprising SiO 2 particles having an average maximum diameter of from about 100 Angstroms to about 500 Angstroms.
Claim 8
Dependent Claim
71 words
The method of planarizing SiO 2 containing dielectric of claim 1 comprising: depositing the layer of undoped SiO 2 by decomposition of tetraethyl orthosilicate to a thickness of at least 2000 Angstroms; and the slurry has a solution component and a solids component, the solution component comprising KOH and water, the solids component comprising SiO 2 particles having an average maximum diameter of from about 100 Angstroms to about 500 Angstroms.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-12-08 | 1996-06-08 | 1996-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-12-08 | 2000-06-08 | 2000-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-12-08 | 2004-06-08 | 2004-12-08 | $7700.00 | Window Closed / Lapsed |