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US20030170565A1 Expired / Lapsed US ⏱️ 0.0 years remaining

Method of removing assist features utilized to improve process latitude

Assignee: ASML Netherlands BV
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Filing: 2002-11-27
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Granted: —
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Expires: 2022-11-27
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Abstract

Abstract A method of transferring a lithographic pattern onto a substrate by use of a lithographic apparatus. The method includes the steps of: (1) defining features to be printed on the substrate; (2) determining which of the features require assist features to be disposed adjacent thereto in order for the features to be printed within defined resolution limits; (3) generating a mask containing the features to be printed and the assist features; (4) performing a first illumination process so as to print the features on the substrate, the first illumination process resulting in the partial printing of the assist features on the substrate; and (5) performing a second illumination process so as to reduce the amount of the assist features printed on the substrate; the second illumination process entails the step of performing a quadrapole illumination.

Inventors

  • 👤 Markus Eurlings
  • 👤 Jang Chen
  • 👤 Duan-Fu Hsu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 12:36
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/70; G03F7/70058; G03F7/70125; H; H10; H10P; H10P76/00; G03F1/00; G03F1/36; G03F1/68; G03F1/70; G03F7/70425; G03F7/70433; G03F7/70441; G03F7/70466

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 132 words
1 . A method of transferring a lithographic pattern onto a substrate by use of a lithographic apparatus, said method comprising the steps of: defining features to be printed on said substrate; determining which of said features require assist features to be disposed adjacent thereto in order for said features to be printed within defined resolution limits; generating a mask containing said features to be printed and said assist features; performing a first illumination process so as to print said features on said substrate, said first illumination process resulting in the partial printing of said assist features on said substrate; and performing a second illumination process so as to reduce the amount of said assist features printed on said substrate; said second illumination process comprising the step of performing a quadrapole illumination.
Claim 2
Dependent Claim 132 words
1 . A method of transferring a lithographic pattern onto a substrate by use of a lithographic apparatus, said method comprising the steps of: defining features to be printed on said substrate; determining which of said features require assist features to be disposed adjacent thereto in order for said features to be printed within defined resolution limits; generating a mask containing said features to be printed and said assist features; performing a first illumination process so as to print said features on said substrate, said first illumination process resulting in the partial printing of said assist features on said substrate; and performing a second illumination process so as to reduce the amount of said assist features printed on said substrate; said second illumination process comprising the step of performing a quadrapole illumination.
Claim 3
Dependent Claim 29 words
2 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein said second illumination process comprises a QUASAR™ illumination.
Claim 4
Dependent Claim 38 words
3 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein the sequence in which said first illumination process and said second illumination process are performed is interchangeable.
Claim 5
Dependent Claim 32 words
4 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein said first illumination process includes a dipole illumination of said substrate.
Claim 6
Dependent Claim 48 words
5 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein said first illumination process includes performing a first exposure of said substrate utilizing a x-dipole illumination, and a second exposure of said substrate utilizing a y-dipole illumination.
Claim 7
Dependent Claim 50 words
6 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein said second illumination process utilizes a mask having a pattern formed therein, which is a biased negative of a pattern defined by the assist features contained in said mask.
Claim 8
Dependent Claim 49 words
7 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein substantially all of said assist features printed on said substrate as a result of said first illumination process are removed from said substrate by said second illumination process.
Claim 9
Dependent Claim 52 words
8 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 1 , wherein said assist features include assist features aligned in a first direction and assist features aligned in a second direction, said first direction and said second direction being orthogonal to one another.
Claim 10
Dependent Claim 45 words
9 . The method of transferring a lithographic pattern onto a substrate according to the method of claim 8 , wherein said second illumination process substantially removes both said assist features aligned in said first direction and said assist features aligned in said second direction.
Claim 11
Dependent Claim 160 words
10 . A device manufacturing method comprising the steps of: providing a substrate that is at least partially covered by a layer of radiation sensitive material; providing a projection beam of radiation using a radiation system; using patterning means to endow the projection beam with a pattern in its cross-section, said patterning means includes features to be printed on said substrate and assist features disposed adjacent at least one of said features to be printed, said assist features performing optical proximity correction; projecting the patterned beam of radiation onto a target portion of the layer of radiation-sensitive material including a first illumination process so as to print said features on said substrate, said first illumination process resulting in the partial printing of said assist features on said substrate; and performing a second illumination process so as to reduce the amount of said assist features printed on said substrate; said second illumination process comprising the step of performing a quadrapole illumination.
Claim 12
Dependent Claim 160 words
10 . A device manufacturing method comprising the steps of: providing a substrate that is at least partially covered by a layer of radiation sensitive material; providing a projection beam of radiation using a radiation system; using patterning means to endow the projection beam with a pattern in its cross-section, said patterning means includes features to be printed on said substrate and assist features disposed adjacent at least one of said features to be printed, said assist features performing optical proximity correction; projecting the patterned beam of radiation onto a target portion of the layer of radiation-sensitive material including a first illumination process so as to print said features on said substrate, said first illumination process resulting in the partial printing of said assist features on said substrate; and performing a second illumination process so as to reduce the amount of said assist features printed on said substrate; said second illumination process comprising the step of performing a quadrapole illumination.
Claim 13
Dependent Claim 19 words
11 . The device manufacturing method of claim 10 , wherein said second illumination process comprises a QUASAR™ illumination.
Claim 14
Dependent Claim 28 words
12 . The device manufacturing method of claim 10 , wherein the sequence in which said first illumination process and said second illumination process are performed is interchangeable.
Claim 15
Dependent Claim 22 words
13 . The device manufacturing method of claim 10 , wherein said first illumination process includes a dipole illumination of said substrate.
Claim 16
Dependent Claim 38 words
14 . The device manufacturing method of claim 10 , wherein said first illumination process includes performing a first exposure of said substrate utilizing a x-dipole illumination, and a second exposure of said substrate utilizing a y-dipole illumination.
Claim 17
Dependent Claim 40 words
15 . The device manufacturing method of claim 10 , wherein said second illumination process utilizes a mask having a pattern formed therein, which is a biased negative of a pattern defined by the assist features contained in said mask.
Claim 18
Dependent Claim 39 words
16 . The device manufacturing method of claim 10 , wherein substantially all of said assist features printed on said substrate as a result of said first illumination process are removed from said substrate by said second illumination process.
Claim 19
Dependent Claim 42 words
17 . The device manufacturing method of claim 10 , wherein said assist features include assist features aligned in a first direction and assist features aligned in a second direction, said first direction and said second direction being orthogonal to one another.
Claim 20
Dependent Claim 35 words
18 . The device manufacturing method of claim 17 , wherein said second illumination process substantially removes both said assist features aligned in said first direction and said assist features aligned in said second direction.

References Cited (Backward Citations)

US5900340A Cited
US20020004175A1 Cited
US6519760B2 Cited
US20020192570A1 Cited

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