US5527744A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wafer method for breaking a semiconductor
Assignee: Texas Instruments Inc
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Filing: 1994-11-21
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Granted: 1996-06-18
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Expires: 2014-11-21
Abstract
Abstract A process for partially sawing the streets on semiconductor wafers. After sawing the streets can be covered by a protective material, and then the wafer continues its processing as before. After the wafer is broken, the protective material may or may not be removed. Additionally, the wafer may be broken into individual chips using a wedge piece that has a number of individual wedges on it, where the individual wedges press against the partially sawn streets, causing the wafer to break.
Inventors
- 👤 Michael A. Mignardi
- 👤 Rafael C. Alfaro
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:00
CPC Classifications
B; B81; B81C; B81C1/00; B81C1/00865; B81C1/00896; B28; B28D; B28D5/00; B28D5/0005; B28D5/0011; B28D5/0017; B28D5/0023; B28D5/0041; B28D5/0047; H; H10; H10P; H10P52/00; H10P54/00; Y; Y10; Y10S; Y10S148/00; Y10S148/028; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1062; Y10T156/1064; Y10T225/00; Y10T225/10; Y10T225/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
171 words
A method for processing and handling semiconductor wafers comprising the steps of: a. partially sawing streets in a wafer upon which are partially processed micromechanical devices including structures supported above said wafer by a sacrificial layer; b. covering said streets with a protective coating such that said protective coating does not interfere with said micromechanical devices or said sacrificial layer; c. processing said wafer such that said sacrificial layer is removed thereby allowing said micromechanical devices to move freely and exposing surfaces underneath said micromechanical devices; d. positioning a wedge piece with a plurality of wedges adjacent said wafer such that said wedges are aligned along said partially sawn streets without any of said wedges being in contact with said wafer; e. applying pressure to force said wafer against said wedges causing said wafer to break into chips along said partially sawn streets, wherein said protective coating prevents any debris from said breaking from coming into contact with any of said surfaces underneath said micromechanical devices; and f. removing said chips.
Claim 2
Independent Claim
171 words
A method for processing and handling semiconductor wafers comprising the steps of: a. partially sawing streets in a wafer upon which are partially processed micromechanical devices including structures supported above said wafer by a sacrificial layer; b. covering said streets with a protective coating such that said protective coating does not interfere with said micromechanical devices or said sacrificial layer; c. processing said wafer such that said sacrificial layer is removed thereby allowing said micromechanical devices to move freely and exposing surfaces underneath said micromechanical devices; d. positioning a wedge piece with a plurality of wedges adjacent said wafer such that said wedges are aligned along said partially sawn streets without any of said wedges being in contact with said wafer; e. applying pressure to force said wafer against said wedges causing said wafer to break into chips along said partially sawn streets, wherein said protective coating prevents any debris from said breaking from coming into contact with any of said surfaces underneath said micromechanical devices; and f. removing said chips.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said protective coating is tape.
Claim 4
Dependent Claim
11 words
The process of claim 1 wherein said protective coating is caulking.
Claim 5
Dependent Claim
14 words
The process of claim 1 further comprises the step of removing the protective material.
Claim 6
Dependent Claim
35 words
The process of claim 1 wherein said sawing step includes mounting said wafer to a saw frame, and said wafer remains on said saw frame throughout said sawing, covering, processing, positioning, applying and removing steps.
Claim 7
Dependent Claim
32 words
The process of claim 1 wherein said sawing step includes mounting said wafer to a saw frame, and then demounting said water from said saw frame after said sawing step is completed.
Claim 8
Dependent Claim
22 words
The process of claim 1 wherein said applying pressure further comprises applying a vacuum to force said wafer against said wedge piece.
Claim 9
Dependent Claim
23 words
The process of claim 1 wherein said applying pressure further comprises using a mechanical arm to push said wafer against said wedge piece.
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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) | 1999-06-18 | 1999-12-18 | 2000-06-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-06-18 | 2003-12-18 | 2004-06-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-06-18 | 2007-12-18 | 2008-06-18 | $7700.00 | Window Closed / Lapsed |