Patent EP0383534A2 successfully refreshed from Google Patents.
← Back to Patent Explorer
EP0383534A2 Expired / Lapsed EP ⏱️ 0.0 years remaining

Exposure mask, method of manufacturing the same, and exposure method using the same

Assignee: Toshiba Corp
•
Filing: 1990-02-13
•
Granted: —
•
Expires: 2010-02-13
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An exposure mask for lithography, a method of manufacturing the same, and an exposure method using the same are disclosed. A light-transmitting opening of the exposure mask has a main light-transmitting region located in the middle of the opening and having a first optical path length, and phase shift regions adjacent to a light-shielding layer and having a second optical path length, different from the first optical path length. Light transmitted through each phase shift region interferes with light transmitted through the main light-transmitting region at the edges of the light-­transmitting opening, thus enabling a sharp photo-­intensity distribution of total transmitted light to be obtained. As a result, the resolution of the exposure mask is improved.

Inventors

  • 👤 Akihiro C/O Intellectual Property Div. Nitayama
  • 👤 Makoto C/O Intellectual Property Div. Nakase
  • 👤 Kouji C/O Intellectual Property Div. Hasimoto
  • 👤 Hirotsugu C/O Intellectual Property Div. Wada

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-30 20:11
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/26; G03F1/29

Claims Analysis

Total Claims: 30
Claim 1
Independent Claim 52 words
An exposure mask for lithography, comprising: a optically transparent substrate; and a light-shielding layer on said optically transpar­ent substrate, said light-shielding layer being pat­terned to form a single or a plurality of predetermined light-transmitting openings, and each of said light-­transmitting openings having means for obtaining a sharp photo-intensity distribution of transmitted light.
Claim 2
Dependent Claim 52 words
An exposure mask for lithography, comprising: a optically transparent substrate; and a light-shielding layer on said optically transpar­ent substrate, said light-shielding layer being pat­terned to form a single or a plurality of predetermined light-transmitting openings, and each of said light-­transmitting openings having means for obtaining a sharp photo-intensity distribution of transmitted light.
Claim 3
Dependent Claim 58 words
A mask according to claim 1, characterized in that said light-transmitting opening comprises a main light-transmitting region located in the middle thereof, and a phase shift region adjacent to said light-­shielding layer, a phase of light which is transmitted through said phase shift region being shifted from that of light which is transmitted through said main light-­transmitting region.
Claim 4
Dependent Claim 52 words
A mask according to claim 2, characterized in that said light-transmitting opening comprises a main light-transmitting region located in the middle thereof and having a first optical path length, and a phase shift region adjacent to said light-shielding layer and having a second optical path length, different from the first optical length.
Claim 5
Dependent Claim 37 words
A mask according to claim 2, characterized in that a phase of light which is transmitted through said phase shift region is shifted by 180° from that of light which is transmitted through said main light-­transmitting region.
Claim 6
Dependent Claim 29 words
A mask according to claim 3, characterized in that said main light-transmitting region is formed by etching down said optically transparent substrate with respect to said phase shift region.
Claim 7
Dependent Claim 25 words
A mask according to claim 3, characterized in that said phase shift region is formed by arranging an additional light-transmitting layer in said light-transmitting opening.
Claim 8
Dependent Claim 39 words
A mask according to claim 6, characterized in that said additional light-transmitting layer is arranged between said optically transparent substrate and said light-shielding layer, a portion of said light-­transmitting layer protruding from said light-shielding layer into said light-transmitting opening.
Claim 9
Dependent Claim 34 words
A mask according to claim 6, characterized in that said additional light-transmitting layer is formed on said light-shielding layer, a portion of said light-­transmitting layer protruding from said light-shielding layer into said light-transmitting opening.
Claim 10
Dependent Claim 34 words
A mask according to claim 6, characterized in that said additional light-transmitting layer is formed on substantially the same plane as that of said light-­shielding layer, and is present only in said light-­transmitting opening.
Claim 11
Dependent Claim 24 words
A mask according to claim 1, characterized in that said substrate is formed in the shape of a convex lens, in said light-transmitting opening.
Claim 12
Dependent Claim 61 words
A mask according to claim 3, for exposing an object having a first portion, and a second portion which is farther from said mask than the first portion and having a difference in level, wherein a phase shift amount at a first light-transmitting opening for the first portion is larger than that at a second light-­transmitting opening for the second portion.
Claim 13
Independent Claim 220 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent substrate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, said light-­transmitting opening being constituted by a main light-transmitting region located in the middle thereof, and a phase shift region adjacent to said light-­shielding layer, and a phase of light which is transmitted through said phase shift region being shifted from that of light which is transmitted through said main light-transmitting region, said method com­prising the steps of: forming said light-shielding layer on a optically transparent material layer; forming a first film on said light-shielding layer; forming a resist layer on said first film; patterning said resist layer in correspondence with said light-transmitting opening; etching said light-shielding layer and said first film to a surface of said optically transparent material layer by using the patterned resist layer as a mask; removing said resist layer and covering said opti­cally transparent material layer, said light-shielding layer, and said first film with a second film; anisotropically etching said second film so as to leave said second film on only side walls of said light-­shielding layer and said first film; and forming said phase shift region by using the rem­nants of the second film.
Claim 14
Independent Claim 220 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent substrate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, said light-­transmitting opening being constituted by a main light-transmitting region located in the middle thereof, and a phase shift region adjacent to said light-­shielding layer, and a phase of light which is transmitted through said phase shift region being shifted from that of light which is transmitted through said main light-transmitting region, said method com­prising the steps of: forming said light-shielding layer on a optically transparent material layer; forming a first film on said light-shielding layer; forming a resist layer on said first film; patterning said resist layer in correspondence with said light-transmitting opening; etching said light-shielding layer and said first film to a surface of said optically transparent material layer by using the patterned resist layer as a mask; removing said resist layer and covering said opti­cally transparent material layer, said light-shielding layer, and said first film with a second film; anisotropically etching said second film so as to leave said second film on only side walls of said light-­shielding layer and said first film; and forming said phase shift region by using the rem­nants of the second film.
Claim 15
Dependent Claim 85 words
A method according to claim 12, for forming said main light-transmitting region by etching down said optically transparent substrate with respect to said phase shift region, wherein said optically transparent material layer comprises said optically transparent substrate, and the step of forming said phase shift region by using the remnants of the second film com­prises the steps of etching said optically transparent substrate by a predetermined amount, using the remnants of the first and second films as masks, and removing said first and second films.
Claim 16
Dependent Claim 114 words
A method according to claim 12, for forming said phase shift region by arranging an additional light-transmitting layer between said optically trans­parent substrate and said light-shielding layer, a portion of said additional light-transmitting layer protruding into said light-transmitting opening, wherein said optically transparent material layer comprises said additional light-transmitting layer arranged on said optically transparent substrate and having a predeter­mined thickness, and the step of forming said phase shift region by using the remnants of the second film comprises the steps of etching said additional light-­transmitting layer to a surface of said optically trans­parent substrate by using the remnants of the first and second films as masks, and removing said first and sec­ond films.
Claim 17
Dependent Claim 130 words
A method according to claim 12, for forming said phase shift region by arranging an additional light-transmitting layer on substantially the same plane as that of said light-shielding layer and situated only in said light-transmitting opening, wherein said opti­cally transparent material layer comprises said opti­cally transparent substrate, said second film consists of a optically transparent material, and the step of forming said phase shift region by using the remnants of the second film comprises the steps of forming a second resist layer on the remnants of the first and second films, etching said first and second films and said sec­ond resist layer to a surface of said light-shielding layer, and removing said second resist layer so as to leave the remnants of the second film as said additional light-transmitting layer.
Claim 18
Independent Claim 153 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent substrate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, each of said light-­transmitting openings being constituted by a main light-transmitting region located in the middle thereof, and a phase shift region adjacent to said light-­shielding layer, and a phase of light which is transmitted through said phase shift region being shifted from that of light which is transmitted through said main light-transmitting region, said method com­prising the steps of: forming said light-shielding layer on a optically transparent material layer; forming a first film on said light-shielding layer; patterning said first film in correspondence with said main light-transmitting region of said light-­transmitting opening; and overetching said light-shielding layer to the posi­tion of said light-transmitting opening, using the pat­terned first film as a mask.
Claim 19
Independent Claim 153 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent substrate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, each of said light-­transmitting openings being constituted by a main light-transmitting region located in the middle thereof, and a phase shift region adjacent to said light-­shielding layer, and a phase of light which is transmitted through said phase shift region being shifted from that of light which is transmitted through said main light-transmitting region, said method com­prising the steps of: forming said light-shielding layer on a optically transparent material layer; forming a first film on said light-shielding layer; patterning said first film in correspondence with said main light-transmitting region of said light-­transmitting opening; and overetching said light-shielding layer to the posi­tion of said light-transmitting opening, using the pat­terned first film as a mask.
Claim 20
Dependent Claim 63 words
A method according to claim 16, for forming said phase shift region by arranging an additional light-transmitting layer on said light-shielding layer, a portion of said additional light-transmitting layer protruding in to said light-transmitting opening, wherein said optically transparent material layer com­prises said optically transparent substrate, and said first film consists of a optically transparent resist material and constitutes said additional light-­transmitting layer.
Claim 21
Dependent Claim 91 words
A method according to claim 16, for forming said phase shift region by arranging an additional light-transmitting layer on said light-shielding layer, a portion of said additional light-transmitting layer protruding into said light-transmitting opening, wherein said optically transparent material layer comprises said optically transparent substrate, said first film con­sists of a optically transparent material, and the step of patterning said first film comprises the steps of forming a resist layer on said first film, patterning said resist layer, and etching said first film, using the patterned resist layer as a mask.
Claim 22
Dependent Claim 93 words
A method according to claim 16, for forming said phase shift region by arranging an additional light-transmitting layer on said light-shielding layer, a portion of said additional light-transmitting layer protruding into said light-transmitting opening, wherein said optically transparent material layer comprises said optically transparent substrate, said first film con­sists of a optically transparent resist material and constitutes said additional light-transmitting layer, said light-shielding layer is patterned prior to forma­tion of said first film, and exposure for said first film to be patterned is performed from a rear side of said optically transparent substrate.
Claim 23
Dependent Claim 92 words
A method according to claim 16, for forming said phase shift region by arranging an additional light-transmitting layer between said optically trans­parent substrate and said light-shielding layer, a por­tion of said additional light-transmitting layer protruding into said light-transmitting opening, wherein said optically transparent material layer comprises said additional light-transmitting layer having a predeter­mined thickness and which is arranged on said optically transparent substrate, said first film consists of a resist material, and said method further comprises the step of etching said transparent material layer, using the patterned first film on a mask.
Claim 24
Independent Claim 188 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent sub­strate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, and said substrate being formed in the shape of a convex lens, in said light-transmitting opening, said method comprising the steps of: forming said light-shielding layer on said optically transparent substrate; forming a first film on said light-shielding layer; forming a resist layer on said first film; patterning said resist layer in correspondence with said light-transmitting opening; etching said light-shielding layer and said opti­cally transparent substrate, using the patterned resist layer as a mask; removing said resist layer and covering said opti­cally transparent substrate, said light-shielding layer, and said first film with a second film; isotropically etching said second film so as to leave said second film only on side walls of said light-­shielding layer and said first film and a portion of said substrate located in the middle of said light-­transmitting opening; and further etching said optically transparent subs­trate by using the remnants of the second film.
Claim 25
Independent Claim 188 words
A method of manufacturing an exposure mask for lithography, which includes a optically transparent sub­strate and a light-shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of predeter­mined light-transmitting openings, and said substrate being formed in the shape of a convex lens, in said light-transmitting opening, said method comprising the steps of: forming said light-shielding layer on said optically transparent substrate; forming a first film on said light-shielding layer; forming a resist layer on said first film; patterning said resist layer in correspondence with said light-transmitting opening; etching said light-shielding layer and said opti­cally transparent substrate, using the patterned resist layer as a mask; removing said resist layer and covering said opti­cally transparent substrate, said light-shielding layer, and said first film with a second film; isotropically etching said second film so as to leave said second film only on side walls of said light-­shielding layer and said first film and a portion of said substrate located in the middle of said light-­transmitting opening; and further etching said optically transparent subs­trate by using the remnants of the second film.
Claim 26
Dependent Claim 62 words
An exposure method for lithography, character­ized in that said method makes use of an exposure mask including a optically transparent substrate and a light-­shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of light-transmitting openings, and each of said light-transmitting openings including means for obtaining a sharp photo-intensity distribution of transmitted light.
Claim 27
Dependent Claim 62 words
An exposure method for lithography, character­ized in that said method makes use of an exposure mask including a optically transparent substrate and a light-­shielding layer on said optically transparent substrate, said light-shielding layer being patterned to form a single or a plurality of light-transmitting openings, and each of said light-transmitting openings including means for obtaining a sharp photo-intensity distribution of transmitted light.
Claim 28
Dependent Claim 53 words
A method according to claim 22, characterized in that said light-transmitting opening comprises a main light-transmitting region located in the middle thereof and having a first optical path length, and a phase shift region adjacent to said light-shielding layer and having a second optical path length, different from the first optical path length.
Claim 29
Dependent Claim 24 words
A method according to claim 22, characterized in that said substrate is formed in the shape of a con­vex lens, in said light-transmitting opening.
Claim 30
Dependent Claim 69 words
A method according to claim 22, for exposing an object having a first portion, and a second portion which is farther from an exposure mask than said first portion and having a difference in level, wherein the exposure mask is formed in which a phase shift amount at a first light-transmitting opening for said first por­tion is larger than that at a second light-transmitting opening for said second portion.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Maintenance schedule is calculated for granted US utility patents.

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag