US5439764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mask having multiple patterns
Assignee: Microchip Technology Inc
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Filing: 1993-07-01
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Granted: 1995-08-08
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Expires: 2013-07-01
Abstract
Abstract One embodiment of the invention includes multiple patterns on a single mask, where all the patterns on the single mask are used for forming a single product. In the preferred embodiment, each of four quadrants of a mask have a different process layer pattern, where each of the four patterns is associated with a different process layer for the same product. After exposure of the wafer using the mask, the mask is rotated 90° for the next exposure step so that the mask pattern image for the next layer to be formed on the wafer will overlie the designated quadrant of the wafer which will contain the final product. Although, by using this technique, three-quarters of the wafer will be unusable, this partial waste of the wafer will be offset by the savings in mask costs with low volume production, in prototyping situations, and in product debugging. Using the above technique, conventional mask exposure machines may be used.
Inventors
- 👤 Martin J. Alter
- 👤 Lawrence R. Sample
- 👤 Hiu F. Ip
- 👤 Marty E. Garnett
- 👤 Helmuth R. Litfin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:28
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70425; G03F1/00; G03F1/50
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
130 words
A mask structure for selectively exposing a photoresist layer on a semiconductor wafer surface to radiation, said mask structure comprising: a first section containing an array of identical adjacent first mask patterns for selectively exposing a first section of said wafer to said radiation when said mask structure is in a first position relative to said wafer; and a second section containing an array of identical adjacent second mask patterns, said second mask patterns being different from said first mask patterns, for selectively exposing said first section of said wafer to said radiation when said mask structure is in a second position relative to said wafer, wherein each of said first mask patterns and each of said second mask patterns are for forming a pattern on a single integrated circuit.
Claim 2
Dependent Claim
130 words
A mask structure for selectively exposing a photoresist layer on a semiconductor wafer surface to radiation, said mask structure comprising: a first section containing an array of identical adjacent first mask patterns for selectively exposing a first section of said wafer to said radiation when said mask structure is in a first position relative to said wafer; and a second section containing an array of identical adjacent second mask patterns, said second mask patterns being different from said first mask patterns, for selectively exposing said first section of said wafer to said radiation when said mask structure is in a second position relative to said wafer, wherein each of said first mask patterns and each of said second mask patterns are for forming a pattern on a single integrated circuit.
Claim 3
Dependent Claim
99 words
The mask structure of claim 1 wherein said first mask patterns and said second mask pattern are formed on said mask structure so that an image of said first mask patterns impinges upon said first section of said wafer when said mask structure is interposed between a source of said radiation and said wafer and, when said mask structure is rotated through a predetermined angle relative to said wafer, an image of said second mask patterns impinges upon said first section of said wafer when said mask structure is interposed between said source of said radiation and said wafer.
Claim 4
Dependent Claim
12 words
The mask structure of claim 2 wherein said predetermined angle is 90°.
Claim 5
Dependent Claim
12 words
The mask structure of claim 2 wherein said predetermined angle is 180°.
Claim 6
Dependent Claim
12 words
The mask structure of claim 2 wherein said predetermined angle is 270°.
Claim 7
Dependent Claim
53 words
The mask structure of claim 2 wherein said first section of said mask structure is a first quadrant of said mask structure and said second section of said mask structure is a second quadrant of said mask structure, and wherein said first section of said wafer is a single quadrant of said wafer.
Claim 8
Dependent Claim
119 words
The mask structure of claim 6 further comprising an array of identical adjacent third mask patterns and an array of identical adjacent fourth mask patterns wherein said first mask patterns are contained in a first quadrant of said mask structure, said second mask patterns are contained in a second quadrant of said mask structure, said third mask patterns are contained in a third quadrant of said mask structure, and said fourth mask patterns are contained in a fourth quadrant of said mask structure, each of said first, second, third, and fourth mask patterns being different from the other, wherein each of said first, second, third, and fourth mask patterns are for forming a pattern on a single integrated circuit.
Claim 9
Dependent Claim
32 words
The mask pattern of claim 7 wherein each of said first mask patterns, second mask patterns, third mask patterns, and fourth mask patterns overlap into an adjacent quadrant of said mask structure.
Claim 10
Dependent Claim
54 words
The mask structure of claim 1 wherein said first mask patterns and said second mask patterns define patterns to be formed in two or more photoresist layers for forming a single integrated circuit product, said first mask patterns and said second mask patterns being required in the formation of said single integrated circuit product.
Claim 11
Dependent Claim
26 words
The mask structure of claim 9 wherein said first mask patterns and said second mask patterns are variations on a same layer defined on said wafer.
Claim 12
Dependent Claim
38 words
The mask structure of claim 1 wherein said first mask patterns are used in the formation of a first integrated circuit product, and said second mask patterns are used in the formation of a second integrated circuit product.
Claim 13
Dependent Claim
98 words
The mask structure of claim 1 wherein said first mask patterns and said second mask patterns are formed on said mask structure so that an image of said first mask patterns impinges upon said first section of said wafer when said mask structure is interposed between the source of said radiation and said wafer and, when said mask structure is shifted a predetermined amount relative to said wafer, an image of said second mask patterns impinges upon said first section of said wafer when said mask structure is interposed between said source of said radiation and said wafer.
Claim 14
Dependent Claim
19 words
The mask structure of claim 12 wherein said predetermined amount is approximately equal to or less than 90 mils.
Claim 15
Dependent Claim
24 words
The mask structure of claim 12 wherein said first mask patterns and said second mask pattern alternate along a surface of said mask structure.
Claim 16
Independent Claim
123 words
A method for forming integrated circuit devices comprising the steps of: positioning a mask structure in a first relative position between a radiation source and a semiconductor wafer so that an array of identical adjacent first patterns formed on said mask structure causes a corresponding image to impinge on a first section of said wafer to selectively expose said first section to said radiation; and positioning said mask structure in a second relative position between said source of radiation and said wafer so that an array of identical adjacent second patterns, different from said first patterns, formed on said mask structure causes a corresponding image to impinge on said first section of said wafer to selectively expose said first section to said radiation.
Claim 17
Independent Claim
123 words
A method for forming integrated circuit devices comprising the steps of: positioning a mask structure in a first relative position between a radiation source and a semiconductor wafer so that an array of identical adjacent first patterns formed on said mask structure causes a corresponding image to impinge on a first section of said wafer to selectively expose said first section to said radiation; and positioning said mask structure in a second relative position between said source of radiation and said wafer so that an array of identical adjacent second patterns, different from said first patterns, formed on said mask structure causes a corresponding image to impinge on said first section of said wafer to selectively expose said first section to said radiation.
Claim 18
Dependent Claim
31 words
The method of claim 15 wherein said step of positioning said mask structure in said second relative position comprises rotating said mask structure through a predetermined angle relative to said wafer.
Claim 19
Dependent Claim
12 words
The mask structure of claim 16 wherein said predetermined angle is 90°.
Claim 20
Dependent Claim
12 words
The mask structure of claim 16 wherein said predetermined angle is 180°.
Claim 21
Dependent Claim
54 words
The method of claim 15 wherein said first patterns on said mask structure reside in a first quadrant of said mask structure and said second patterns on said mask structure reside in a second quadrant of said mask structure, and wherein said first section of said wafer is a single quadrant of said wafer.
Claim 22
Dependent Claim
53 words
The method of claim 15 wherein said first mask patterns and said second mask patterns define patterns to be formed in two or more photoresist layers for forming a single integrated circuit product, said first mask patterns and said second mask patterns being required in the formation of said single integrated circuit product.
Claim 23
Dependent Claim
37 words
The method of claim 15 wherein said first mask patterns are used in the formation of a first integrated circuit product, and said second mask patterns are used in the formation of a second integrated circuit product.
Claim 24
Dependent Claim
29 words
The method of claim 15 wherein said first mask patterns and said second mask patterns are two pattern variations for a same layer to be defined on said wafer.
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) | 1998-08-07 | 1999-02-06 | 1999-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-08-07 | 2003-02-06 | 2003-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-08-07 | 2007-02-06 | 2007-08-08 | $7700.00 | Window Closed / Lapsed |