US3970819A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Backside laser dicing system
Assignee: International Business Machines Corp
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Filing: 1974-11-25
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Granted: 1976-07-20
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Expires: 1994-11-25
Abstract
Abstract A wafer of semiconductor material having a plurality of units defined on its face is subdivided by treating the wafer, on its back or reverse side, in the kerf regions between the units, where division of the units is desired, such that the material of the wafer in the treated kerf regions is converted to a material having a breaking strength lower than the breaking strength of the semiconductor material.
Inventors
- 👤 Gerald Alan Gates
- 👤 William John Ryan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:23
CPC Classifications
H; H10; H10P; H10P34/00; H10P34/40; H10P34/42; B; B23; B23K; B23K26/00; B23K26/36; B23K26/40; B28; B28D; B28D5/00; B28D5/0005; B28D5/0011; B28D5/0017; B28D5/0029; B23K2101/00; B23K2101/36; B23K2101/40; B23K2103/00; B23K2103/50; H10W; H10W72/00; H10W72/20; Y; Y10; Y10T; Y10T225/00; Y10T225/10; Y10T225/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
130 words
A process for breaking along predetermined lines a wafer of single crystal material having a given thickness and selected breaking strength comprising the steps of, applying a laser beam along said lines, said laser beam having an intensity sufficient to convert all the thickness of the wafer along said lines into a continuous non-crystalline material extending through the thickness of the wafer and having a breaking strength less than the breaking strength of the single crystal material, converting a portion of said wafer extending through said given thickness and defined by said lines into said non-crystalline material, removing said beam,and separating the wafer into individual units by applying a force to said wafer sufficient to exceed the breaking strength of the non-crystalline material but insufficient to break the crystalline material.
Claim 2
Dependent Claim
130 words
A process for breaking along predetermined lines a wafer of single crystal material having a given thickness and selected breaking strength comprising the steps of, applying a laser beam along said lines, said laser beam having an intensity sufficient to convert all the thickness of the wafer along said lines into a continuous non-crystalline material extending through the thickness of the wafer and having a breaking strength less than the breaking strength of the single crystal material, converting a portion of said wafer extending through said given thickness and defined by said lines into said non-crystalline material, removing said beam,and separating the wafer into individual units by applying a force to said wafer sufficient to exceed the breaking strength of the non-crystalline material but insufficient to break the crystalline material.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein said wafer of single crystal material is comprised of silicon.
Claim 4
Dependent Claim
12 words
The process of claim 2 wherein said non-crystalline material comprises silicon dioxide.
Claim 5
Dependent Claim
54 words
the process of claim 1 wherein said wafer of single crystal material is comprised of semiconductor material and has first and second major surfaces with a plurality of integrated circuits separated by kerf areas disposed on said first surface, and said laser beam is applied to said second surface and in said kerf areas.
Claim 6
Dependent Claim
32 words
The process of claim 1 wherein said laser beam is derived from a yittrium aluminum garnet, niobium doped continuous laser having an average power of 16 watts in the third order mode.
Claim 7
Dependent Claim
14 words
The process of claim 5 wherein said laser beam is pulsed at 12.5 KC.
Claim 8
Dependent Claim
32 words
The process of claim 1 wherein said laser beam is applied along said lines by mounting the wafer on a movable table under said beam and moving said table under said beam.
Claim 9
Dependent Claim
22 words
The process of claim 7 wherein said wafer is moved under said laser beam at the rate of 1 inch per second.
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) | 1979-07-20 | 1980-01-19 | 1980-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-07-20 | 1984-01-19 | 1984-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-07-20 | 1988-01-19 | 1988-07-20 | $7700.00 | Window Closed / Lapsed |