US4127437A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for etching SiO2 utilizing HF vapor and an organic catalyst
Assignee: Branson International Plasma Corp
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Filing: 1977-09-01
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Granted: 1978-11-28
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Expires: 1997-09-01
Abstract
Abstract Process for etching SiO 2 with hydrogen fluoride gas, utilizing an organic material such as negative photoresist as a catalyst. In one embodiment, the negative photoresist is applied directly to the portions of the SiO 2 to be removed, and in another the negative photoresist is spaced away from the SiO 2 . In some embodiments, positive photoresist is applied to the portions of the SiO 2 which are to be retained.
Inventors
- 👤 Richard L. Bersin
- 👤 James H. Junkin
- 👤 Richard F. Reichelderfer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 14:43
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283; H10P50/73; Y; Y10; Y10S; Y10S438/00; Y10S438/942; Y10S438/948
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
63 words
In a process for removing SiO 2 from a substrate member, the steps of: placing an organic catalyst containing hydrogen and carbon but substantially no oxygen in in direct contact with the surface of the SiO 2 to be removed, and exposing the catalyst to hydrogen fluoride gas which permeates through the catalyst for a time sufficient to remove the SiO 2 .
Claim 2
Dependent Claim
63 words
In a process for removing SiO 2 from a substrate member, the steps of: placing an organic catalyst containing hydrogen and carbon but substantially no oxygen in in direct contact with the surface of the SiO 2 to be removed, and exposing the catalyst to hydrogen fluoride gas which permeates through the catalyst for a time sufficient to remove the SiO 2 .
Claim 3
Dependent Claim
13 words
The process of claim 1 wherein the organic catalyst is a negative photoresist.
Claim 4
Dependent Claim
38 words
The process of claim 1 further including the step of exposing portions of the SiO 2 not covered by the organic catalyst to a gas plasma to condition said portions to resist etching by the hydrogen fluoride gas.
Claim 5
Dependent Claim
41 words
The process of claim 1 further including the step of applying positive photoresist over portions of the SiO 2 to be retained, the organic catalyst being applied over the positive photoresist and the portions of the SiO 2 to be removed.
Claim 6
Dependent Claim
18 words
The process of claim 1 further including the step of placing a metal backing behind the substrate member.
Claim 7
Dependent Claim
24 words
The process of claim 1 wherein the substrate is placed in a chamber heated to a temperature on the order of 150° C-200° C.
Claim 8
Dependent Claim
22 words
The process of claim 1 wherein the removal of SiO 2 is effected at a pressure on the order of 3-7 torr.
Claim 9
Dependent Claim
57 words
In a process for removing SiO 2 from a substrate member, the steps of disposing an organic catalyst containing hydrogen and carbon but substantially no oxygen spaced from and generally parallel to the surface of the SiO 2 and exposing the SiO 2 to hydrogen fluoride gas for a time sufficient to remove the SiO 2 .
Claim 10
Dependent Claim
57 words
In a process for removing SiO 2 from a substrate member, the steps of disposing an organic catalyst containing hydrogen and carbon but substantially no oxygen spaced from and generally parallel to the surface of the SiO 2 and exposing the SiO 2 to hydrogen fluoride gas for a time sufficient to remove the SiO 2 .
Claim 11
Dependent Claim
13 words
The process of claim 8 wherein the organic catalyst is a negative photoresist.
Claim 12
Dependent Claim
16 words
The process of claim 8 further including the step placing a metal backing behind the substrate.
Claim 13
Dependent Claim
24 words
The process of claim 8 wherein the substrate is placed in a chamber heated to a temperature on the order of 150° C-200° C.
Claim 14
Dependent Claim
22 words
The process of claim 8 wherein the removal of SiO 2 is effected at a pressure on the order of 3-7 Torr.
Claim 15
Dependent Claim
64 words
In a process for removing SiO 2 from a substrate member in a chamber, the steps of: placing negative photoresist over the portions of the SiO 2 to be removed, heating the chamber to a temperature on the order of 150° C.-200° C., and exposing the SiO 2 to hydrogen fluoride gas for a time sufficient to remove the SiO 2 beneath the photoresist.
Claim 16
Dependent Claim
64 words
In a process for removing SiO 2 from a substrate member in a chamber, the steps of: placing negative photoresist over the portions of the SiO 2 to be removed, heating the chamber to a temperature on the order of 150° C.-200° C., and exposing the SiO 2 to hydrogen fluoride gas for a time sufficient to remove the SiO 2 beneath the photoresist.
Claim 17
Dependent Claim
40 words
The process of claim 13 including the additional step of exposing the SiO 2 to a gas plasma to condition the portion of the SiO 2 not covered by the negative photoresist to resist etching by the hydrogen fluoride gas.
Claim 18
Dependent Claim
91 words
In a process for removing SiO 2 from a substrate member in a chamber, the steps of: providing a mask of positive photoresist over a portion of the SiO 2 which is to be retained, applying a layer of negative photoresist over a portion of the SiO 2 which is to be removed, heating the chamber to a temperature on the order of 150° C.-200° C. and exposing the structure to hydrogen fluoride gas to effect etching of the portion of the SiO 2 in direct contact with the negative photoresist.
Claim 19
Dependent Claim
91 words
In a process for removing SiO 2 from a substrate member in a chamber, the steps of: providing a mask of positive photoresist over a portion of the SiO 2 which is to be retained, applying a layer of negative photoresist over a portion of the SiO 2 which is to be removed, heating the chamber to a temperature on the order of 150° C.-200° C. and exposing the structure to hydrogen fluoride gas to effect etching of the portion of the SiO 2 in direct contact with the negative photoresist.
Claim 20
Dependent Claim
31 words
The process of claim 15 further including the step of heating the positive photoresist to a predetermined temperature to repolymerize the same prior to the application of the negative photoresist layer.
Claim 21
Dependent Claim
104 words
In a process for producing a predetermined pattern of SiO 2 on a semiconductor wafer, the steps of: forming a layer of SiO 2 on a semiconductor substrate, providing a mask of positive photoresist over the SiO 2 layer with windows exposing portions of the SiO 2 to be removed to form the pattern, placing a layer of negative photoresist in facing relationship with the exposed portions of the SiO 2 and spaced therefrom, and introducing hydrogen fluoride gas into the space between the layer of negative photoresist and the SiO 2 to effect etching of the exposed portions of the SiO 2 .
Claim 22
Dependent Claim
104 words
In a process for producing a predetermined pattern of SiO 2 on a semiconductor wafer, the steps of: forming a layer of SiO 2 on a semiconductor substrate, providing a mask of positive photoresist over the SiO 2 layer with windows exposing portions of the SiO 2 to be removed to form the pattern, placing a layer of negative photoresist in facing relationship with the exposed portions of the SiO 2 and spaced therefrom, and introducing hydrogen fluoride gas into the space between the layer of negative photoresist and the SiO 2 to effect etching of the exposed portions of the SiO 2 .
Claim 23
Dependent Claim
17 words
The process of claim 17 wherein a metal plate is positioned behind the substrate during the etching.
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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) | 1981-11-27 | 1982-05-29 | 1982-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-27 | 1986-05-29 | 1986-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-27 | 1990-05-29 | 1990-11-28 | $7700.00 | Window Closed / Lapsed |