US4519846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for washing and drying a semiconductor element
Assignee: Individual
•
Filing: 1984-03-08
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Granted: 1985-05-28
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Expires: 2004-03-08
Abstract
Abstract After subjecting a semiconductor element to etching, it must be washed with water and then dried so as to remove any etchant therefrom. In the course of the washing and drying steps, the semiconductor element may undergo quality changes due to its contact with water. Such quality changes become remarkable when the semiconductor element is kept for a long time period in the resultant washings. The above quality changes can be successfully avoided by holding an etched semiconductor element horizontally over a water-washing tank, pre-washing its downwardly-directed front surface with an upward jet of water, thoroughly washing the front surface with pure water blown upwardly from a lower part of the tank while washing its upwardly-directed rear surface with water so that both surfaces of the semiconductor element are washed completely, and then immediately spin-drying the thus-washed semiconductor element.
Inventors
- 👤 Seiichiro Aigo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:19
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0402; H10P72/0406; H10P72/0411; H10P72/0414; Y; Y10; Y10S; Y10S134/00; Y10S134/902
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
134 words
A process for washing and drying a semiconductor element wherein one surface of the element has been subjected to etching, which process comprises: (a) holding the semiconductor element horizontally with the etched surface directed downwards over a water-washing tank having essentially vertical side walls and a dished bottom and pre-washing the etched surface of the semiconductor element with water jetted out from water nozzles provided in the tank; (b) washing the etched surface with pure water by blowing the pure water upwardly against said etched surface from a port in the bottom of the tank; (c) while washing the etched surface with pure water, simultaneously washing the other, upwardly-facing, surface of the semiconductor element by causing water to fall onto the upwardly-facing surface; and then (d) spinning the semiconductor element to spin-dry the same.
Claim 2
Dependent Claim
134 words
A process for washing and drying a semiconductor element wherein one surface of the element has been subjected to etching, which process comprises: (a) holding the semiconductor element horizontally with the etched surface directed downwards over a water-washing tank having essentially vertical side walls and a dished bottom and pre-washing the etched surface of the semiconductor element with water jetted out from water nozzles provided in the tank; (b) washing the etched surface with pure water by blowing the pure water upwardly against said etched surface from a port in the bottom of the tank; (c) while washing the etched surface with pure water, simultaneously washing the other, upwardly-facing, surface of the semiconductor element by causing water to fall onto the upwardly-facing surface; and then (d) spinning the semiconductor element to spin-dry the same.
Claim 3
Dependent Claim
58 words
A process as claimed in claim 1, wherein the process comprises a further step of blowing gas against the upwardly-facing surface of the semiconductor element to dry the same after washing the same with water in step (c), and conducting step (d) while holding the semiconductor element by its upwardly-facing surface on a carrier by means of suction.
Claim 4
Dependent Claim
26 words
A process as claimed in claim 1, wherein the washing of the upwardly-facing surface of the semiconductor element is conducted by showering water onto the same.
Claim 5
Dependent Claim
38 words
A process as claimed in claim 3, wherein the washing of the upwardly-facing surface with the shower of water is carried out after the washing of the etched surface with upwardly-blown water has proceeded to a predetermined extent.
Claim 6
Dependent Claim
37 words
A process as claimed in claim 1, wherein the spin-drying step (d) is carried out after turning the semiconductor element upside down by an inverting machine and then mounting the thus-inverted semiconductor element on a spinning machine.
Claim 7
Dependent Claim
23 words
A process as claimed in claim 1, wherein the water-washing step (b) of the etched surface is carried out with heated pure water.
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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) | 1988-05-27 | 1988-11-26 | 1989-05-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-05-27 | 1992-11-26 | 1993-05-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-05-27 | 1996-11-26 | 1997-05-28 | $7700.00 | Window Closed / Lapsed |