US5567332A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Micro-machine manufacturing process
Assignee: Tel Manufacturing and Engineering of America Inc
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Filing: 1995-06-09
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Granted: 1996-10-22
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Expires: 2015-06-09
Abstract
Abstract A gaseous process for removing and vaporizing at least a portion of a silicon oxide film from between a substrate and a superstructure leaving a space between the substrate and the superstructure. The silicon oxide layer is removed in two steps. In the first step the bulk of the silicon oxide layer is removed by a rapid liquid or gaseous etching process, leaving at least a portion of the silicon oxide layer directly underlying the superstructure in place so as to support the superstructure during a wash cycle. In the second silicon oxide removal step the substrate is introduced to a high flow rate gaseous environment containing a relatively high concentration of anhydrous HF to which no, or only a relatively very low amount of, additional water vapor is provided until the silicon oxide directly underlying the superstructure has been removed.
Inventors
- 👤 Jitesh Mehta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:08
CPC Classifications
H; H10; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/282; H10P50/283
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
151 words
A manufacturing process for producing a three dimensional structure on a substrate, in which said structure has been built up of silicon on the substrate, with at least a portion of the structure overlying and supported by a layer of a silicon oxide on the substrate, the process comprising removing the silicon oxide layer in two steps, the first step comprising removing the bulk of the silicon oxide layer by a rapid liquid or gaseous etching process, leaving at least a portion of the silicon oxide layer directly underlying the structure in place so as to support the structure during a wash cycle, and the second silicon oxide removal step comprising introducing the substrate to a high flow rate gaseous environment containing anhydrous HF, said flow rate being at least about 20 liters/min, to which substantially no water is provided until the silicon oxide directly underlying the structure has been removed.
Claim 2
Dependent Claim
151 words
A manufacturing process for producing a three dimensional structure on a substrate, in which said structure has been built up of silicon on the substrate, with at least a portion of the structure overlying and supported by a layer of a silicon oxide on the substrate, the process comprising removing the silicon oxide layer in two steps, the first step comprising removing the bulk of the silicon oxide layer by a rapid liquid or gaseous etching process, leaving at least a portion of the silicon oxide layer directly underlying the structure in place so as to support the structure during a wash cycle, and the second silicon oxide removal step comprising introducing the substrate to a high flow rate gaseous environment containing anhydrous HF, said flow rate being at least about 20 liters/min, to which substantially no water is provided until the silicon oxide directly underlying the structure has been removed.
Claim 3
Dependent Claim
36 words
The process according to claim 1 further comprising, between said first and second steps, subjecting the substrate to a wash cycle to remove reactant chemicals and/or reaction by-products of the first step and drying the substrate.
Claim 4
Dependent Claim
23 words
The process according to claim 1 wherein the first step comprises introducing the substrate to hydrogen fluoride gas in the presence of water.
Claim 5
Dependent Claim
27 words
The process of claim 3 wherein in the first step, an anhydrous hydrogen fluoride gas and water are mixed just prior to introduction thereof to the substrate.
Claim 6
Dependent Claim
23 words
The process of claim 3 wherein in the first step, the anhydrous hydrogen fluoride gas is carried in a dry inert carrier gas.
Claim 7
Dependent Claim
16 words
The process of claim 1 wherein in the second step HF concentration is at least 1%.
Claim 8
Dependent Claim
13 words
The process according to claim 1 wherein the substrate is a silicon wafer.
Claim 9
Dependent Claim
18 words
The process of claim 7 wherein the reaction temperature in the second step is at least 18° C.
Claim 10
Dependent Claim
14 words
The process according to claim 7 wherein the structure comprises polysilicon or amorphous silicon.
References Cited (Backward Citations)
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US5177661A
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US5043043A
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US5093594A
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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) | 1999-10-22 | 2000-04-22 | 2000-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-10-22 | 2004-04-22 | 2004-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-10-22 | 2008-04-22 | 2008-10-22 | $7700.00 | Window Closed / Lapsed |