US5157000A
Expired / Lapsed
US
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Method for dry etching openings in integrated circuit layers
Assignee: Texas Instruments Inc
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Filing: 1991-02-08
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Granted: 1992-10-20
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Expires: 2011-02-08
Abstract
Abstract A process is disclosed through which vias (50) can be formed by the reaction of an etchant species (52) with a mercury cadmium telluride (HgCdTe) or zinc sulfide (ZnS) layer (42). The activating gases (20) are preferably a hydrogen gas or a methane gas which is excited in a diode plasma reactor (100) which has an RF power source (13) applied to one of two parallel electrodes. The etching occurs in selected areas in a photoresist pattern (44) residing over the ZnS or HgCdTe layer (42). Wet etching the layer (42) with a wet etchant (54) following the dry etching, improves the via (50) by making the walls (48) smoother, and allowing for expansion of the vias (50) to a dimension necessary for proper operation of a HgCdTe-based infrared detector.
Inventors
- 👤 Jerome L. Elkind
- 👤 Patricia B. Smith
- 👤 Larry D. Hutchins
- 👤 Joseph D. Luttmer
- 👤 Rudy L. York
- 👤 Julie S. England
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:10
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/69; H10P52/00; H10P95/00; H10P95/70; Y; Y10; Y10S; Y10S148/00; Y10S148/051
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
94 words
A method for forming openings in a wafer made of Group II and Group VI elements in a vacuum plasma reactor comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing a methylradical liberating hydrocarbon into the reactor; dry etching the openings in the wafer by forming activated methylradicals in an in situ generated plasma to etch the openings; removing the wafer from the vacuum plasma reactor; wet etching the openings in the wafer to smooth and expand the openings to a selected dimension; and removing the photoresist layer.
Claim 2
Independent Claim
94 words
A method for forming openings in a wafer made of Group II and Group VI elements in a vacuum plasma reactor comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing a methylradical liberating hydrocarbon into the reactor; dry etching the openings in the wafer by forming activated methylradicals in an in situ generated plasma to etch the openings; removing the wafer from the vacuum plasma reactor; wet etching the openings in the wafer to smooth and expand the openings to a selected dimension; and removing the photoresist layer.
Claim 3
Dependent Claim
11 words
The method of claim 1, wherein the wafer comprises zinc sulfide.
Claim 4
Dependent Claim
12 words
The method of claim 1, wherein the wafer comprises mercury cadmium telluride.
Claim 5
Dependent Claim
12 words
The method of claim 1, wherein the photoresist is a NOVOLAK™ composition.
Claim 6
Dependent Claim
19 words
The method of claim 1, wherein said step of wet etching comprises spray-etching a bromine-methanol solution onto the wafer.
Claim 7
Independent Claim
86 words
A method for forming openings in a wafer made of Group II and Group VI elements in a vacuum plasma reactor, comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing hydrogen gas into the reactor; dry etching the openings in the wafer with hydrogenradicals formed by in situ plasma generation; removing the wafer from the vacuum plasma reactor; wet etching the openings in the wafer to smooth and expand the openings to a selected dimension; and removing the photoresist pattern.
Claim 8
Independent Claim
86 words
A method for forming openings in a wafer made of Group II and Group VI elements in a vacuum plasma reactor, comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing hydrogen gas into the reactor; dry etching the openings in the wafer with hydrogenradicals formed by in situ plasma generation; removing the wafer from the vacuum plasma reactor; wet etching the openings in the wafer to smooth and expand the openings to a selected dimension; and removing the photoresist pattern.
Claim 9
Dependent Claim
11 words
The method of claim 6, wherein the wafer comprises zinc sulfide.
Claim 10
Dependent Claim
12 words
The method of claim 6, wherein the wafer comprises mercury cadmium telluride.
Claim 11
Dependent Claim
12 words
The method of claim 6, wherein said photoresist is a NOVOLAK™ composition.
Claim 12
Dependent Claim
19 words
The method of claim 6, wherein said step of wet etching comprises spray-etching a bromine-methanol solution onto the wafer.
Claim 13
Independent Claim
94 words
A method for forming sidewalls in a wafer made of Group II and Group VI elements in a vacuum plasma reactor comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing a methylradical liberating hydrocarbon into the reactor; dry etching the sidewalls in the wafer by forming activated methylradicals in an in situ generated plasma to etch the sidewalls; removing the wafer from the vacuum plasma reactor; wet etching the sidewalls in the wafer to smooth and expand the sidewalls to a selected dimension; and removing the photoresist layer.
Claim 14
Independent Claim
94 words
A method for forming sidewalls in a wafer made of Group II and Group VI elements in a vacuum plasma reactor comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing a methylradical liberating hydrocarbon into the reactor; dry etching the sidewalls in the wafer by forming activated methylradicals in an in situ generated plasma to etch the sidewalls; removing the wafer from the vacuum plasma reactor; wet etching the sidewalls in the wafer to smooth and expand the sidewalls to a selected dimension; and removing the photoresist layer.
Claim 15
Dependent Claim
11 words
The method of claim 11, wherein the wafer comprises zinc sulfide.
Claim 16
Dependent Claim
12 words
The method of claim 11, wherein the wafer comprises mercury cadmium telluride.
Claim 17
Dependent Claim
12 words
The method of claim 11, wherein the photoresist is a NOVOLAK™ composition.
Claim 18
Dependent Claim
19 words
The method of claim 11, wherein said step of wet etching comprises spray-etching a bromine-methanol solution onto the wafer.
Claim 19
Independent Claim
86 words
A method for forming sidewalls in a wafer made of Group II and Group VI elements in a vacuum plasma reactor, comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing hydrogen gas into the reactor; dry etching the sidewall in the wafer with hydrogenradicals formed by in situ plasma generation; removing the wafer from the vacuum plasma reactor; wet etching the sidewalls in the wafer to smooth and expand the sidewalls to a selected dimension; and removing the photoresist pattern.
Claim 20
Independent Claim
86 words
A method for forming sidewalls in a wafer made of Group II and Group VI elements in a vacuum plasma reactor, comprising the steps of: forming a photoresist pattern on the surface of the wafer; introducing hydrogen gas into the reactor; dry etching the sidewall in the wafer with hydrogenradicals formed by in situ plasma generation; removing the wafer from the vacuum plasma reactor; wet etching the sidewalls in the wafer to smooth and expand the sidewalls to a selected dimension; and removing the photoresist pattern.
Claim 21
Dependent Claim
11 words
The method of claim 16, wherein the wafer comprises zinc sulfide.
Claim 22
Dependent Claim
12 words
The method of claim 16, wherein the wafer comprises mercury cadmium telluride.
Claim 23
Dependent Claim
12 words
The method of claim 16, wherein said photoresist is a NOVOLAK™ composition.
Claim 24
Dependent Claim
19 words
The method of claim 16, wherein said step of wet etching comprises spray-etching a bromine-methanol solution onto the wafer.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1995-10-20 | 1996-04-20 | 1996-10-20 | $2000.00 | Window Closed / Lapsed |
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