US3918150A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for separating a semiconductor wafer into discrete pellets
Assignee: General Electric Co
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Filing: 1974-02-08
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Granted: 1975-11-11
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Expires: 1994-02-08
Abstract
Abstract This invention relates to a system for separating a semiconductor wafer into a plurality of discrete pellets while maintaining the relative orientation that the pellets exhibited when in the wafer. The invention is carried out by first applying a ductile variable coupling layer to a surface of the wafer. The coupling layer is affixed to a stretchable membrane which, after the wafer is subdivided, is stretched to space the pellets from one another. The coupling material adheres more tightly to the membrane than to the wafer. A portion of the bond between the ductile coupling layer and the membrane is broken during stretch so that the pellets adhere less tightly to the coupling layer following stretch than prior thereto.
Inventors
- 👤 Francis C Gantley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 19:04
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0442; B; B28; B28D; B28D5/00; B28D5/0005; B28D5/0052; H10P72/70; H10P72/74; H10P72/7402; H10P72/7416; Y; Y10; Y10T; Y10T225/00; Y10T225/10; Y10T225/12; Y10T225/30; Y10T225/371; Y10T29/00; Y10T29/49; Y10T29/49789; Y10T29/4979
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
114 words
A method of manufacturing semiconductor devices comprising the steps of: providing a semiconductor wafer which defines two major surfaces and has been diffused so as to form, upon subdivision, a plurality of semiconductor pellets; adhering to one of said major surfaces a layer of ductile variable coupling material, said ductile material being applied as a liquid and then cured; affixing to said coupling material a stretchable membrane that adheres to said coupling material more strongly than said coupling material adheres to said wafer; subdividing said wafer; stretching said membrane in all directions so as to separate said pellets while maintaining the same relative orientation among said pellets; and removing said pellets from said wafer.
Claim 2
Independent Claim
114 words
A method of manufacturing semiconductor devices comprising the steps of: providing a semiconductor wafer which defines two major surfaces and has been diffused so as to form, upon subdivision, a plurality of semiconductor pellets; adhering to one of said major surfaces a layer of ductile variable coupling material, said ductile material being applied as a liquid and then cured; affixing to said coupling material a stretchable membrane that adheres to said coupling material more strongly than said coupling material adheres to said wafer; subdividing said wafer; stretching said membrane in all directions so as to separate said pellets while maintaining the same relative orientation among said pellets; and removing said pellets from said wafer.
Claim 3
Dependent Claim
22 words
A method according to claim 1 wherein said substep of applying comprises the substep of centrifuging said wafer to distribute said liquid.
Claim 4
Dependent Claim
13 words
A method according to claim 1 wherein said one major surface is rough.
Claim 5
Dependent Claim
57 words
A method according to claim 1 wherein said step of stretching said membrane comprises the substep of breaking the adhesion between said layer of coupling material and each of said pellets in the area around the periphery of each of said pellets such that the adhesion between each of said pellets and said coupling layer is reduced.
Claim 6
Dependent Claim
20 words
A method according to claim 1 wherein said affixing step is carried out at an elevated temperature of approximately 225*F.
Claim 7
Dependent Claim
24 words
A method according to claim 1 wherein said membrane comprises an adhesive layer for adhering said membrane and said layer of ductile coupling material.
Claim 8
Dependent Claim
22 words
A method according to claim 1 wherein said step of individually removing said pellets is carried out with a vacuum pickup probe.
Claim 9
Dependent Claim
19 words
A method according to claim 1 wherein said layer of ductile Coupling material comprises a layer of synthetic resin.
Claim 10
Dependent Claim
21 words
A method according to claim 1 wherein said layer of ductile coupling material is from 0.1 to 0.5 mils in thickness.
References Cited (Backward Citations)
US3537169A
Cited
US3714704A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-10 | 1979-05-12 | 1979-11-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-10 | 1983-05-12 | 1983-11-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-10 | 1987-05-12 | 1987-11-11 | $7700.00 | Window Closed / Lapsed |