Patent US5146104A successfully refreshed from Google Patents.
EP0265584A2
Expired / Lapsed
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Method and materials for etching silicon dioxide using silicon nitride or silicon rich dioxide as an etch barrier
Assignee: International Business Machines Corp
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Filing: 1987-05-05
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Granted: —
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Expires: 2007-05-05
Abstract
Abstract A process for etching SiO2 using either silicon rich SiO2 or Si2N4 as an etching barrier over a substrate. Selectivity is obtained between the two dielectric materials, silicon dioxide and silicon nitride or silicon dioxide and silicon rich silicon dioxide wherein the oxide etches considerably faster than nitride (or silicon rich silicon dioxide) because of the selectivity of oxide to nitride. A further object of the present invention is to provide an etching process wherein the silicon dioxide on the substrate is directionally etched in a fluorocarbon gas to form silicon dioxide spacers on a substrate, and the substrate surface ist protected by an etch stop composed of the silicon nitride or silicon rich silicon dioxide material.
Inventors
- 👤 Reid Stuart Bennett
- 👤 Hu Herbert Chao
- 👤 Paul Edward Sackles
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 03:12
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
144 words
A process for etching a layer of silicon dioxide disposed on a semiconductor substrate employing a layer of silicon rich material as an etch barrier comprising the steps of: 1) over a semiconductor substrate having regions of material on the surface thereof including vertical sidewall surfaces, normal to said substrate surface, disposing a tirst layer ot material having a silicon content substantially greater than the amount of silicon content in silicon dioxide; 2) disposing a layer of silicon dioxide over said first layer; 3) directionally etching said silicon dioxide layer in a direction normal to said substrate surface to remove said silicon dioxide except for regions disposed on said vertical sidewall surfaces, wherein said first layer disposed under said silicon dioxide layer is etched at a slower rate relative to said silicon dioxide to function as an etch barrier over said semiconductor substrate surface.
Claim 2
Dependent Claim
144 words
A process for etching a layer of silicon dioxide disposed on a semiconductor substrate employing a layer of silicon rich material as an etch barrier comprising the steps of: 1) over a semiconductor substrate having regions of material on the surface thereof including vertical sidewall surfaces, normal to said substrate surface, disposing a tirst layer ot material having a silicon content substantially greater than the amount of silicon content in silicon dioxide; 2) disposing a layer of silicon dioxide over said first layer; 3) directionally etching said silicon dioxide layer in a direction normal to said substrate surface to remove said silicon dioxide except for regions disposed on said vertical sidewall surfaces, wherein said first layer disposed under said silicon dioxide layer is etched at a slower rate relative to said silicon dioxide to function as an etch barrier over said semiconductor substrate surface.
Claim 3
Dependent Claim
15 words
A process according to Claim 1 wherein said tirst layer is composed of silicon nitride.
Claim 4
Dependent Claim
36 words
A process according to Claim 1 wherein said first layer is composed of silicon dioxide having an amount of silicon content substantially greater than the amount of silicon in said silicon dioxide layer of step 2.
Claim 5
Dependent Claim
27 words
A process according to Claim 1 wherein said silicon dioxide layer is directionally etched by reactive ion etching in a CClF 3 + H 2 gas environment.
Claim 6
Dependent Claim
14 words
A process according to Claim 1 wherein said semiconductor substrate is composed of silicon.
Claim 7
Dependent Claim
15 words
A process according to Claim 1 wherein said semiconductor substrate is composed of gallium arsenide.
Claim 8
Dependent Claim
35 words
A process according to Claim 2 wherein said semiconductor substrate is composed of silicon and wherein the disposition of said silicon nitride layer is preceded by the deposition ot a passivating layer of silicon dioxide.
Claim 9
Dependent Claim
19 words
A process according to Claim 1 wherein, after step 3, said first etch barrier layer is removed by etching.
References Cited (Backward Citations)
No citation records indexed.
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