US3915784A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of semiconductor chip separation
Assignee: International Business Machines Corp
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Filing: 1972-04-26
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Granted: 1975-10-28
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Expires: 1992-04-26
Abstract
Abstract Disclosed is a method and apparatus for separating discrete chips of a diced semiconductor wafer without disturbing the orientation of the chips, the chips being bonded to a support or substrate from which they must be separated prior to use. The substrate is first positioned in a fixture so that the diced wafer assumes a predetermined orientation, and then a resilient foraminous pad is pressed against the chips, and a bond releasing fluid is urged, by a novel pump, through the pad until the chips are released from their support, the thickness of the removed bond being compensated for by expansion of the pad. Also disclosed is a fixture which acts as a convenient storage tray for the chips in their original orientation.
Inventors
- 👤 Manik P Makhijani
- 👤 Frank Scacciaferro
- 👤 Carl Yakubowski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:24
CPC Classifications
H; H10; H10P; H10P52/00; Y; Y10; Y10S; Y10S156/00; Y10S156/918; Y10S156/93; Y10S156/931; Y10S156/932; Y10T; Y10T156/00; Y10T156/19; Y10T156/1978; Y10T156/1983
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
114 words
A METHOD OF SEPARARING DISCRETE CHIPS OF A DICED SEMICONDUCTOR WAFER FROM A SUBSTRATE TO WHICH THEY ARE BONDED BY A FLUID RELEASABLE BOND WITHOUT DISTURBING THE ORIENTATION OF SAID CHIPS, SAID CHIP HAVING OPEN SPACES THEREBETWEEN DIFINING A KERF AREA, COMPRISING THE STEPS OF: PLACING A RESILIENT PAD AGAINST SAID SEMICONDUCTOR CHIPS, SAID PAD HAVING TWO SETS OF APERATURE THEREIN, ONE SET ALIGNED WITH SAID CHIPS AND A SECOND SET ALIGNED WITH SAID KERF AREAS, PLACING SAID SUBSTRATE AND PAD IN A CONTAINER OF BOND RELEASING FLUID AND EFFECTING AN OSCILLATORY PUMPING OF SAID BOND RELEASING FLUID THROUGH AT LEAST SAID SECOND SET OF APERTURES AGAINST SAID BOND UNTIL SAID BOND IS DESTROYED.
Claim 2
Independent Claim
114 words
A METHOD OF SEPARARING DISCRETE CHIPS OF A DICED SEMICONDUCTOR WAFER FROM A SUBSTRATE TO WHICH THEY ARE BONDED BY A FLUID RELEASABLE BOND WITHOUT DISTURBING THE ORIENTATION OF SAID CHIPS, SAID CHIP HAVING OPEN SPACES THEREBETWEEN DIFINING A KERF AREA, COMPRISING THE STEPS OF: PLACING A RESILIENT PAD AGAINST SAID SEMICONDUCTOR CHIPS, SAID PAD HAVING TWO SETS OF APERATURE THEREIN, ONE SET ALIGNED WITH SAID CHIPS AND A SECOND SET ALIGNED WITH SAID KERF AREAS, PLACING SAID SUBSTRATE AND PAD IN A CONTAINER OF BOND RELEASING FLUID AND EFFECTING AN OSCILLATORY PUMPING OF SAID BOND RELEASING FLUID THROUGH AT LEAST SAID SECOND SET OF APERTURES AGAINST SAID BOND UNTIL SAID BOND IS DESTROYED.
Claim 3
Independent Claim
135 words
A method of separating discrete chips of a diced semiconductor wafer without disturbing their orientation, said chips being bonded to a substrate, comprising the steps of: positioning said substrate in a fixture; orienting said substrate to align said chips in a predetermined orientation; clamping said substrate in said predetermined orientation; compressing a resilient pad having a first group of apertures aligned with said chips and a second group of apertures intermediate said chips, against said chips and clamping said pad relative to said chips to form an assembly with said fixture; positioning said assembly in registry with the output of a pump, submerging said assembly in a container of bond releasing medium and effecting, by said pump, an oscillation of said bond destroying medium through said second group of apertures until said bond is destroyed.
Claim 4
Independent Claim
135 words
A method of separating discrete chips of a diced semiconductor wafer without disturbing their orientation, said chips being bonded to a substrate, comprising the steps of: positioning said substrate in a fixture; orienting said substrate to align said chips in a predetermined orientation; clamping said substrate in said predetermined orientation; compressing a resilient pad having a first group of apertures aligned with said chips and a second group of apertures intermediate said chips, against said chips and clamping said pad relative to said chips to form an assembly with said fixture; positioning said assembly in registry with the output of a pump, submerging said assembly in a container of bond releasing medium and effecting, by said pump, an oscillation of said bond destroying medium through said second group of apertures until said bond is destroyed.
Claim 5
Dependent Claim
43 words
A method in accordance with claim 2 including the steps of: removing said assembly from said tank, drawing a vacuum on said first group of apertures to hold said chips in position on said pad, and removing said substrate while maintaining a vacuum.
Claim 6
Dependent Claim
17 words
A method in accordance with claim 3 including the step of clamping a cover over said chips.
References Cited (Backward Citations)
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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) | 1978-10-27 | 1979-04-28 | 1979-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-27 | 1983-04-28 | 1983-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-27 | 1987-04-28 | 1987-10-28 | $7700.00 | Window Closed / Lapsed |