Patent US5605489A successfully refreshed from Google Patents.
US5605489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of protecting micromechanical devices during wafer separation
Assignee: Texas Instruments Inc
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Filing: 1995-05-23
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Granted: 1997-02-25
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Expires: 2015-05-23
Abstract
Abstract A processing fixture and method of fabricating micromechanical devices, such as digital micromirror devices, that allows fragile structures on wafer 22 to be protected from debris during the saw operation and subsequent cleaning operations. The wafer 22 is attached to a vacuum fixture 26 after partially sawing the wafer 22 to create saw kerfs. The backside of the wafer 22 is then ground down to the saw kerfs 24 to separate the devices 32. Each device 32 is held on the fixture by a vacuum in the headspace above the device 32. In an alternate embodiment the devices are separated by sawing completely through the wafer while in the fixture.
Inventors
- 👤 Richard O. Gale
- 👤 Michael A. Mignardi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:30
CPC Classifications
B; B25; B25B; B25B11/00; B25B11/005; H; H10; H10D; H10D84/00; H10D84/01; B28; B28D; B28D5/00; B28D5/0005; B28D5/0052; B28D5/0058; B28D5/0082; B28D5/0094; B28D5/02; B28D5/022; B81; B81C; B81C1/00; B81C1/00865; B81C1/00888; G; G02; G02B; G02B26/00; G02B26/08; G02B26/0816; G02B26/0833; G02B26/0841; Y; Y10; Y10S; Y10S148/00; Y10S148/028; Y10T; Y10T225/00; Y10T225/10; Y10T225/12
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
80 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: partially sawing between said devices on a first side; placing a protective fixture over and in contact with said first side of said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; grinding the side of said wafer opposite said first side to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 2
Independent Claim
80 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: partially sawing between said devices on a first side; placing a protective fixture over and in contact with said first side of said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; grinding the side of said wafer opposite said first side to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 3
Dependent Claim
25 words
The method of claim 1 wherein said protective fixture is fabricated of a material selected from the group consisting of stainless steel, ceramic, and quartz.
Claim 4
Dependent Claim
14 words
The method of claim 1 wherein said protective fixture is a flexible protective fixture.
Claim 5
Dependent Claim
24 words
The method of claim 1 further comprising the step of cleaning debris created by said grinding step from said devices and said protective fixture.
Claim 6
Dependent Claim
25 words
The method of claim 1 further comprising the step of cleaning debris created by said further processing step from said devices and said protective fixture.
Claim 7
Independent Claim
61 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: placing a flexible protective fixture over and in contact with said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; breaking said wafer to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 8
Independent Claim
61 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: placing a flexible protective fixture over and in contact with said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; breaking said wafer to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 9
Independent Claim
71 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: placing a protective fixture over and in contact with a first side of said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; grinding the side of said wafer opposite said first side to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 10
Independent Claim
71 words
A method of processing a wafer containing one or more micromechanical devices, said method comprising: placing a protective fixture over and in contact with a first side of said wafer, said protective fixture defining a headspace above each device; evacuating said headspace to create a vacuum; grinding the side of said wafer opposite said first side to separate said devices; and removing said vacuum to release said devices from said fixture.
Claim 11
Dependent Claim
25 words
The method of claim 7 wherein said protective fixture is fabricated of a material selected from the group consisting of stainless steel, ceramic, and quartz.
Claim 12
Dependent Claim
14 words
The method of claim 7 wherein said protective fixture is a flexible protective fixture.
Claim 13
Dependent Claim
24 words
The method of claim 7 further comprising the step of cleaning debris created by said grinding step from said devices and said protective fixture.
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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) | 2000-02-25 | 2000-08-26 | 2001-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-02-25 | 2004-08-26 | 2005-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-02-25 | 2008-08-26 | 2009-02-25 | $7700.00 | Window Closed / Lapsed |