US4632557A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alignment target image enhancement for microlithography process
Assignee: Intersil Corp
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Filing: 1985-01-23
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Granted: 1986-12-30
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Expires: 2005-01-23
Abstract
Abstract A reflective target region is surrounded by a substantial light scattering region on a substrate to increase the contrast. The width of any reflective portion of the light scattering region is substantially smaller than the width of the target region along the orthogonal axis of the substrate. The light scattering region includes a plurality of peaks and valleys having parallel axis which are oblique to the axis of the substrate.
Inventors
- 👤 Thomas K. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 04:08
CPC Classifications
G; G03; G03F; G03F9/00; G03F9/70; G03F9/7088; G03F9/7073; G03F9/7076
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
68 words
An alignment target comprising: a substrate; a flat target region of a light reflecting characteristic on said substrate; and a contrast region of a plurality of peaks and valleys contiguous to said target region of a light scattering characteristic on said substrate; the lateral area of said contrast region being substantially greater than the lateral area of said target region to enhance the contrast of said target region.
Claim 2
Dependent Claim
68 words
An alignment target comprising: a substrate; a flat target region of a light reflecting characteristic on said substrate; and a contrast region of a plurality of peaks and valleys contiguous to said target region of a light scattering characteristic on said substrate; the lateral area of said contrast region being substantially greater than the lateral area of said target region to enhance the contrast of said target region.
Claim 3
Dependent Claim
19 words
An alignment target according to claim 1 wherein said target and contrast regions are made of the same material.
Claim 4
Dependent Claim
49 words
An alignment target according to claim 2 wherein said peaks and valleys are each shaped to have an axis which are parallel to each other, said target region includes a first and second portion having orthogonal axes, and said peaks' and valleys' axes are oblique to said orthogonal axes.
Claim 5
Dependent Claim
32 words
An alignment target according to claim 2 wherein the width of any flat portion of each of said peaks and valleys are substantially smaller than the width of said flat target region.
Claim 6
Dependent Claim
39 words
An alignment target according to claim 1 wherein said target region is shaped to have a major axis and said peaks and valleys are shaped each to include an axis which is oblique to said target region's major axis.
Claim 7
Dependent Claim
24 words
An alignment target according to claim 1 wherein the depth of the valley is at least as great as the separation of said ridges.
Claim 8
Dependent Claim
26 words
An alignment target according to claim 6 wherein the width of each of said ridges and valleys are less than the width of said target region.
Claim 9
Dependent Claim
38 words
An alignment target according to claim 1 wherein said substrate includes means for defining orthogonal axes of said substrate and said peaks and valleys are shaped to each include an axis which is oblique to said substrate's axes.
Claim 10
Dependent Claim
39 words
An alignment target according to claim 8 wherein the width of said target region along said substrate's orthogonal axes is substantially greater than the width of any reflective portion of said peaks or valleys along said substrate's orthogonal axes.
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) | 1989-12-29 | 1990-06-30 | 1990-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-12-29 | 1994-06-30 | 1994-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-12-29 | 1998-06-30 | 1998-12-30 | $7700.00 | Window Closed / Lapsed |