US5807649A
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US
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Lithographic patterning method and mask set therefor with light field trim mask
Assignee: International Business Machines Corp
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Filing: 1996-10-31
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Granted: 1998-09-15
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Expires: 2016-10-31
Abstract
Abstract A lithographic patterning method and mask set using a phase shift trim mask having mask dimensions increased in block size so as to remove previous exposure defects.
Inventors
- 👤 Lars W. Liebmann
- 👤 David S. O'Grady
- 👤 Richard A. Ferguson
- 👤 William J. Adair
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:01
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70425; G03F7/70433; H; H10; H10P; H10P76/00; G03F1/00; G03F1/26; G03F1/68; G03F1/70; G03F7/70216; G03F7/70283
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
96 words
Method of patterning a feature in a photosensitive layer, comprising the steps of: exposing said photosensitive layer to a first mask using phase shifting, said first mask including at least one opaque active feature and a radiation transmitting phase shift area adjoining at least a portion of said opaque active feature region to form a phase edge phase shifted mask; and exposing said photosensitive layer to a second mask comprising an opaque trim masking region surrounded by radiation transmitting areas, wherein said second mask exposes said phase shift area and masks said opaque active feature region.
Claim 2
Dependent Claim
96 words
Method of patterning a feature in a photosensitive layer, comprising the steps of: exposing said photosensitive layer to a first mask using phase shifting, said first mask including at least one opaque active feature and a radiation transmitting phase shift area adjoining at least a portion of said opaque active feature region to form a phase edge phase shifted mask; and exposing said photosensitive layer to a second mask comprising an opaque trim masking region surrounded by radiation transmitting areas, wherein said second mask exposes said phase shift area and masks said opaque active feature region.
Claim 3
Dependent Claim
83 words
The method of claim 1, wherein said active feature region has an active feature region shape defined by active region shape side edges and said trim masking region has a trim masking region shape defined by trim masking region shape side edges, wherein said trim masking region shape completely overlaps said active feature region shape, wherein said trim masking region side edges extend a distance beyond said active region side edges of at least one overlay error between said first and second masks.
Claim 4
Dependent Claim
25 words
The method of claim 1, wherein said trim masking region in said second mask is at least about 1.0 Rayleigh units in any x-y direction.
Claim 5
Dependent Claim
44 words
The method of claim 1, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using a subtractive process wherein said substrate is grooved at substrate portions.
Claim 6
Dependent Claim
49 words
The method of claim 1, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using an additive process wherein a phase shift material is deposited on said substrate at substrate portions.
Claim 7
Dependent Claim
14 words
The method of claim 1, wherein said photosensitive layer is a positive photoresist layer.
Claim 8
Independent Claim
158 words
A method for forming a device layer in a photosensitive layer, comprising the steps of: providing a substrate having a first layer and a first photosensitive layer on said first layer; exposing said first photosensitive layer to a first mask using phase shifting to form a first exposure pattern in said photosensitive layer, said first mask including at least one opaque active feature and a radiation transmitting phase shift area adjoining at least a portion of said opaque active feature region to form a phase edge phase shifted mask; exposing said first patterned photosensitive layer to a second mask to form a second exposure pattern in said photosensitive layer, said second mask comprising an opaque trim masking region that masks said active region, said opaque trim masking region surrounded by radiation transmitting areas; developing said first exposure pattern and said second exposure pattern; and removing said photosensitive layer from said first exposure pattern and said second exposure pattern.
Claim 9
Independent Claim
158 words
A method for forming a device layer in a photosensitive layer, comprising the steps of: providing a substrate having a first layer and a first photosensitive layer on said first layer; exposing said first photosensitive layer to a first mask using phase shifting to form a first exposure pattern in said photosensitive layer, said first mask including at least one opaque active feature and a radiation transmitting phase shift area adjoining at least a portion of said opaque active feature region to form a phase edge phase shifted mask; exposing said first patterned photosensitive layer to a second mask to form a second exposure pattern in said photosensitive layer, said second mask comprising an opaque trim masking region that masks said active region, said opaque trim masking region surrounded by radiation transmitting areas; developing said first exposure pattern and said second exposure pattern; and removing said photosensitive layer from said first exposure pattern and said second exposure pattern.
Claim 10
Dependent Claim
84 words
The method of claim 7, wherein said active feature region has an active feature region shape defined by active region shape side edges and said trim masking region has a trim masking region shape defined by trim masking region shape side edges, wherein said trim masking region shape completely overlaps said active feature region shape, wherein said trim masking region side edges extend a distance beyond said active feature region side edges of at least one overlay error between said first and second masks.
Claim 11
Dependent Claim
25 words
The method of claim 7, wherein said trim masking region in said second mask is at least about 1.0 Rayleigh units in any horizontal direction.
Claim 12
Dependent Claim
44 words
The method of claim 7, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using a substractive process wherein said substrate is grooved at substrate portions.
Claim 13
Dependent Claim
49 words
The method of claim 7, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using an additive process wherein a phase shift material is deposited on said substrate at substrate portions.
Claim 14
Dependent Claim
14 words
The method of claim 7, wherein said photosensitive layer is a positive photoresist layer.
Claim 15
Dependent Claim
34 words
The method of claim 7, wherein said opaque active features areas of said first mask and said opaque trim masking region of said second mask comprise metal films formed and patterned upon transparent substrates.
Claim 16
Dependent Claim
23 words
The method of claim 7, wherein said first layer, after said step of removal of said photosensitive layer, comprises an integrated circuit pattern.
Claim 17
Dependent Claim
72 words
A mask set for forming a device layer having active feature regions defined in a photosensitive layer, comprising; a phase shifting mask including at least one opaque region corresponding to active features and a radiation transmitting phase shift area adjoining at least a portion of said first opaque region; a trim mask including an opaque region masking said active feature region, said trim mask opaque region being surrounded by radiation transmitting regions.
Claim 18
Dependent Claim
72 words
A mask set for forming a device layer having active feature regions defined in a photosensitive layer, comprising; a phase shifting mask including at least one opaque region corresponding to active features and a radiation transmitting phase shift area adjoining at least a portion of said first opaque region; a trim mask including an opaque region masking said active feature region, said trim mask opaque region being surrounded by radiation transmitting regions.
Claim 19
Dependent Claim
85 words
The mask set of claim 15, wherein said active feature region has an active feature region shape defined by active region shape side edges and said trim masking region has a trim masking region shape defined by trim masking region shape side edges, wherein said trim masking region shape completely overlaps said active feature region shape, wherein said trim masking region side edges extend a distance beyond said active region side edges of at least one overlay error between said phase shifting and trim masks.
Claim 20
Dependent Claim
27 words
The mask set of claim 15, wherein said trim masking region in said trim mask is at least about 1.0 Rayleigh units wide in any horizontal direction.
Claim 21
Dependent Claim
45 words
The mask set of claim 15, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using a substractive process wherein said substrate is grooved at substrate portions.
Claim 22
Dependent Claim
50 words
The mask set of claim 15, wherein said first phase shifting mask comprises an opaque area defining said active feature region formed on a transparent substrate, wherein said phase shift area is formed using an additive process wherein a phase shift material is deposited on said substrate at substrate portions.
Claim 23
Dependent Claim
15 words
The mask set of claim 15, wherein said photosensitive layer is a positive photoresist layer.
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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) | 2001-09-14 | 2002-03-16 | 2002-09-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2005-09-14 | 2006-03-16 | 2006-09-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2009-09-14 | 2010-03-16 | 2010-09-15 | $7700.00 | Window Closed / Lapsed |