Patent US4581537A successfully refreshed from Google Patents.
US4581537A
Expired / Lapsed
US
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Method for generating inspection patterns
Assignee: International Business Machines Corp
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Filing: 1984-03-23
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Granted: 1986-04-08
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Expires: 2004-03-23
Abstract
Abstract A method of forming inspection patterns for inspecting a workpiece, e.g., for electron beam inspection of optical photomasks. The inspection patterns are formed from the workpiece patterns themselves by applying a first positive windage to the workpiece patterns, inverting the first positive windaged workpiece patterns and applying a second positive windage to the inverted first positive windaged workpiece patterns. The inspection patterns so produced will contain the requisite guard band and the requisite overlap of abutting patterns.
Inventors
- 👤 Wallace J. Guillaume
- 👤 John F. Loughran
- 👤 Jan Rogoyski
- 👤 Robert A. Simpson
- 👤 Edward V. Weber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 16:50
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/38; G03F1/44; G03F1/68; G03F1/82; G03F1/84; H; H01; H01J; H01J37/00; H01J37/30; H01J37/3002; H01J37/3005
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
189 words
A method of inspecting a pattern on a workpiece, said pattern being formed of a plurality of primitive shapes represented by a first set of coordinate data, comprising the steps of: enlarging each of said primitive shapes by applying a first positive windage to said first set of coordinate data to obtain a second set of coordinate data representing a first modified pattern of overlapping shapes; inverting said second set of coordinate data to obtain a third set of coordinate data representing a second modified pattern which is the complement of said first modified pattern; applying a second positive windage to said third set of coordinate data to obtain a fourth set of coordinate data representing a third modified pattern; applying said fourth set of coordinate data to the deflection means of a selective irradiation tool having said workpiece mounted in the target area thereof to cause a beam of radiation produced thereby to scan said workpiece in said third modified pattern represented by said fourth set of coordinate data; and monitoring the radiation backscattered from or transmitted through said workpiece to detect any defects in said workpiece pattern.
Claim 2
Independent Claim
189 words
A method of inspecting a pattern on a workpiece, said pattern being formed of a plurality of primitive shapes represented by a first set of coordinate data, comprising the steps of: enlarging each of said primitive shapes by applying a first positive windage to said first set of coordinate data to obtain a second set of coordinate data representing a first modified pattern of overlapping shapes; inverting said second set of coordinate data to obtain a third set of coordinate data representing a second modified pattern which is the complement of said first modified pattern; applying a second positive windage to said third set of coordinate data to obtain a fourth set of coordinate data representing a third modified pattern; applying said fourth set of coordinate data to the deflection means of a selective irradiation tool having said workpiece mounted in the target area thereof to cause a beam of radiation produced thereby to scan said workpiece in said third modified pattern represented by said fourth set of coordinate data; and monitoring the radiation backscattered from or transmitted through said workpiece to detect any defects in said workpiece pattern.
Claim 3
Dependent Claim
64 words
The method of claim 1, further comprising: inverting said first set of coordinate data before applying said first positive windage thereto to obtain a fifth set of coordinate data representing a fourth modified pattern from said second positive windage step; and applying said fifth set of coordinate data to said selective irradiation tool deflection means to scan said workpiece in said fourth modified pattern.
Claim 4
Dependent Claim
23 words
The method of claim 1 wherein said fourth set of coordinate data is applied to the deflection means of an electron beam tool.
Claim 5
Dependent Claim
62 words
The method of claim 1 wherein said step of applying said first positive windage includes setting the amount of said first positive windage equal to the sum of a predetermined guard band plus one-half of a predetermined overlap for said primitive shapes forming said workpiece pattern, and setting the amount of said second positive windage equal to one-half of said predetermined overlap.
Claim 6
Dependent Claim
23 words
The method of claim 2 wherein said fourth set of coordinate data is applied to the deflection means of an electron beam tool.
Claim 7
Dependent Claim
62 words
The method of claim 2 wherein said step of applying said first positive windage includes setting the amount of said first positive windage equal to the sum of a predetermined guard band plus one-half of a predetermined overlap for said primitive shapes forming said workpiece pattern, and setting the amount of said second positive windage equal to one-half of said predetermined overlap.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-04-07 | 1989-10-07 | 1990-04-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-04-07 | 1993-10-07 | 1994-04-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-04-07 | 1997-10-07 | 1998-04-08 | $7700.00 | Window Closed / Lapsed |