US4009540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of working flat articles
Assignee: US Philips Corp
•
Filing: 1975-03-25
•
Granted: 1977-03-01
•
Expires: 1995-03-25
Abstract
Abstract An article, for example a semiconductor wafer, is temporarily secured to a support without using a cement so that a treatment such as polishing may be carried out. The support has at least one recess and the article is positioned on the recess. The support with the article are then placed in a space in which sub-atmospheric pressure is produced so that gas escapes from the recess. When the sub-atmospheric pressure in the space is removed, the article closes the recess so that sub-atmospheric pressure is maintained there resulting in temporary adhesion of the article to the support.
Inventors
- 👤 Antonius Johannes Mathijs Uijen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:33
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/70; H10P72/74; H10P50/00; H10P72/7402; H10P72/7412; H10P72/7416
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
151 words
A method of temporarily holding together facing connection surfaces of a semiconductor wafer and support for working on a surface of the wafer remote from the support, comprising the steps of: forming in the connection surface of the support at least one recess, said at least one recess being open only at the connection surface and having walls that are gas impermeable; positioning the connection surface of the semiconductor wafer against the connection surface of the support in a position to cover completely the opening of said at least one recess, thereby forming at least one closed space; reducing the gas pressure surrounding the support and wafer until subatmospheric gas pressure is produced in said at least one closed space; and bringing the gas pressure surrounding the support and wafer to atmospheric pressure to trap subatmospheric pressure in said at least one closed space and hold the wafer and support together.
Claim 2
Independent Claim
151 words
A method of temporarily holding together facing connection surfaces of a semiconductor wafer and support for working on a surface of the wafer remote from the support, comprising the steps of: forming in the connection surface of the support at least one recess, said at least one recess being open only at the connection surface and having walls that are gas impermeable; positioning the connection surface of the semiconductor wafer against the connection surface of the support in a position to cover completely the opening of said at least one recess, thereby forming at least one closed space; reducing the gas pressure surrounding the support and wafer until subatmospheric gas pressure is produced in said at least one closed space; and bringing the gas pressure surrounding the support and wafer to atmospheric pressure to trap subatmospheric pressure in said at least one closed space and hold the wafer and support together.
Claim 3
Dependent Claim
38 words
The method defined in claim 1 characterized in that a plurality of recesses are formed in the connection surface of the support and the connection surface of the wafer covers completely the openings of a plurality of recesses.
Claim 4
Dependent Claim
24 words
The method defined in claim 2 characterized in that a plurality of semiconductor wafers are simultaneously held at different positions against the same support.
Claim 5
Dependent Claim
24 words
The method defined in claim 3 wherein the connection surface of the support and the walls of said recesses are formed of synthetic rubber.
Claim 6
Dependent Claim
25 words
The method defined in claim 4 wherein the wafers are removed from the support by again reducing the gas pressure surrounding the support and wafers.
Claim 7
Dependent Claim
23 words
The method defined in claim 5 wherein gravity automatically pulls the wafers from the support when the surrounding gas pressure is sufficiently reduced.
Claim 8
Dependent Claim
27 words
The method defined in claim 1 wherein the connection surface of the support and the walls of said at least one recess are formed of synthetic rubber.
Claim 9
Dependent Claim
44 words
The method defined in claim 1 and further characterized by the step of removing the wafer from the support at a pressure surrounding the support and wafer which is approximately the same as the subatmospheric pressure trapped in said at least one closed space.
Claim 10
Dependent Claim
31 words
The method defined in claim 8 wherein the support and held wafer are positioned such that gravity automatically removes the wafer from the support when the surrounding pressure is sufficiently reduced.
References Cited (Backward Citations)
US2353066A
Cited
US2443987A
Cited
US2855653A
Cited
US3004766A
Cited
US3330714A
Cited
US3131476A
Cited
US3681139A
Cited
US3740900A
Cited
US3809050A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-29 | 1980-08-30 | 1981-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-29 | 1984-08-30 | 1985-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-29 | 1988-08-30 | 1989-03-01 | $7700.00 | Window Closed / Lapsed |