Patent US5457072A successfully refreshed from Google Patents.
US5457072A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for dicing a semiconductor wafer having a plated heat sink using a temporary substrate
Assignee: Mitsubishi Electric Corp
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Filing: 1994-02-15
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Granted: 1995-10-10
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Expires: 2014-02-15
Abstract
Abstract A method for producing semiconductor chips includes preparing a semiconductor wafer having opposite front and rear surfaces and active semiconductor devices disposed in the semiconductor wafer at a part of the front surface, attaching a glass plate to the front surface of the semiconductor wafer, thinning the semiconductor wafer to a desired thickness from the rear surface, forming a first radiating layer over the rear surface of the semiconductor wafer, selectively forming a second radiating layer on the first radiating layer using, as a mask, a photoresist pattern covering portions of the first radiating layer opposite dicing regions, removing the semiconductor wafer from the glass plate, and cutting through the wafer and the first radiating layer with a dicing blade to produce a plurality of semiconductor chips. In this method, since the first radiating layer supports the thin wafer, the glass plate can be removed before the dicing process. Therefore, electrical testing of the semiconductor devices included in the wafer can be carried out before the wafer is divided into chips.
Inventors
- 👤 Masahiro Tamaki
- 👤 Kouji Aono
- 👤 Sinichi Sakamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:14
CPC Classifications
B; B81; B81C; B81C1/00; B81C1/00015; B81C1/00214; H; H10; H10P; H10P52/00; H10P54/00; H10P72/00; H10P72/70; H10P72/74; H10P72/7402; H10P72/7416; Y; Y10; Y10S; Y10S438/00; Y10S438/977
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
164 words
A method for producing semiconductor chips comprising: preparing a semiconductor wafer having opposite front and rear surfaces and active semiconductor devices disposed in said semiconductor wafer at portions of the front surface; attaching a glass plate to the front surface of said semiconductor wafer and grinding said semiconductor wafer from the rear surface to a given thickness; forming a first radiating layer on the rear surface of said semiconductor wafer; forming a film harder and thinner than said first radiating layer on said first radiating layer; forming a second radiating layer on said harder and thinner film using a photoresist pattern masking portions of said harder and thinner film opposite dicing regions of said semiconductor wafer; removing said semiconductor wafer from said glass plate and rinsing the front surface of said semiconductor wafer; and cutting through said semiconductor wafer, said first radiating layer, and said harder and thinner film with a dicing blade at the dicing regions to produce a plurality of semiconductor chips.
Claim 2
Independent Claim
164 words
A method for producing semiconductor chips comprising: preparing a semiconductor wafer having opposite front and rear surfaces and active semiconductor devices disposed in said semiconductor wafer at portions of the front surface; attaching a glass plate to the front surface of said semiconductor wafer and grinding said semiconductor wafer from the rear surface to a given thickness; forming a first radiating layer on the rear surface of said semiconductor wafer; forming a film harder and thinner than said first radiating layer on said first radiating layer; forming a second radiating layer on said harder and thinner film using a photoresist pattern masking portions of said harder and thinner film opposite dicing regions of said semiconductor wafer; removing said semiconductor wafer from said glass plate and rinsing the front surface of said semiconductor wafer; and cutting through said semiconductor wafer, said first radiating layer, and said harder and thinner film with a dicing blade at the dicing regions to produce a plurality of semiconductor chips.
Claim 3
Dependent Claim
29 words
The method of claim 1 wherein said first radiating layer comprises Au and said film harder and thinner than said first radiating layer comprises one of Cr and Fe.
Claim 4
Dependent Claim
19 words
The method of claim 2 including forming said film harder and thinner than said first radiating layer by electroplating.
Claim 5
Independent Claim
173 words
A method for producing semiconductor chips comprising: preparing a semiconductor wafer having opposite front and rear surfaces and active semiconductor devices disposed in said semiconductor wafer at portions of the front surface; attaching a glass plate to the front surface of said semiconductor wafer and grinding said semiconductor wafer from the rear surface to a given thickness; forming a first radiating layer on the rear surface of said semiconductor wafer; forming a second radiating layer on the first radiating layer using a photoresist pattern masking portions of the first radiating layer opposite dicing regions of said semiconductor wafer; forming a film harder and thinner than said first radiating layer on portions of said first radiating layer, which portions are exposed by removing said photoresist pattern; removing said semiconductor wafer from said glass plate and rinsing the front surface of said semiconductor wafer; and cutting through said semiconductor wafer, said first radiating layer, and said harder and thinner film with a dicing blade at the dicing regions to produce a plurality of semiconductor chips.
Claim 6
Independent Claim
173 words
A method for producing semiconductor chips comprising: preparing a semiconductor wafer having opposite front and rear surfaces and active semiconductor devices disposed in said semiconductor wafer at portions of the front surface; attaching a glass plate to the front surface of said semiconductor wafer and grinding said semiconductor wafer from the rear surface to a given thickness; forming a first radiating layer on the rear surface of said semiconductor wafer; forming a second radiating layer on the first radiating layer using a photoresist pattern masking portions of the first radiating layer opposite dicing regions of said semiconductor wafer; forming a film harder and thinner than said first radiating layer on portions of said first radiating layer, which portions are exposed by removing said photoresist pattern; removing said semiconductor wafer from said glass plate and rinsing the front surface of said semiconductor wafer; and cutting through said semiconductor wafer, said first radiating layer, and said harder and thinner film with a dicing blade at the dicing regions to produce a plurality of semiconductor chips.
Claim 7
Dependent Claim
29 words
The method of claim 4 wherein said first radiating layer comprises Au and said film harder and thinner than said first radiating layer comprises one of Cr and Fe.
Claim 8
Dependent Claim
24 words
The method of claim 4 including forming said film harder and thinner than said first radiating layer by deposition and lift-off techniques or electroplating.
References Cited (Backward Citations)
US3946334A
Cited
JPS5571022A
Cited
US4956697A
Cited
US5324981A
Cited
US5138439A
Cited
JPH03232253A
Cited
US5200641A
Cited
US5275958A
Cited
US5302554A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-10-09 | 1999-04-10 | 1999-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-10-09 | 2003-04-10 | 2003-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-10-09 | 2007-04-10 | 2007-10-10 | $7700.00 | Window Closed / Lapsed |