Patent US5926257A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5926257A Expired / Lapsed US ⏱️ 0.0 years remaining

Illumination optical system and exposure apparatus having the same

Assignee: Canon Inc
•
Filing: 1997-07-22
•
Granted: 1999-07-20
•
Expires: 2017-07-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An illumination optical system includes a first diffraction optical element, a second diffraction optical element and a condenser lens. The first diffraction optical element has a plurality of micro diffraction optical elements, which have a first optical power in a first direction and an optical power different from the first optical power in a second direction, perpendicular to the first direction. The second diffraction optical element has a plurality of micro diffraction optical elements, which have a second optical power in the second direction and an optical power different from the second optical power in the first direction. The first optical power is different from the second optical power. Light supplied from a light source forms a plurality of secondary light sources by passing through the first and second diffraction optical elements. Light from the secondary light sources passing through the condenser lens generates Kohler illumination on a surface to be irradiated.

Inventors

  • 👤 Satoru Mizouchi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 11:32
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/09; G02B27/0938; G02B27/0944; G02B27/42; G02B27/4205; G02B27/4222; G02B27/4272; G02B27/4277; G03; G03F; G03F7/00; G03F7/70; G03F7/70058; G03F7/70216; G03F7/70358

Claims Analysis

Total Claims: 21
Claim 1
Independent Claim 142 words
An illumination optical system comprising: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and an optical power different from the second optical power in the first direction, wherein light supplied from a light source forms a plurality of secondary light sources by passing through said first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated.
Claim 2
Dependent Claim 142 words
An illumination optical system comprising: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and an optical power different from the second optical power in the first direction, wherein light supplied from a light source forms a plurality of secondary light sources by passing through said first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated.
Claim 3
Dependent Claim 52 words
A system according to claim 1, wherein the plurality of micro diffraction optical elements of said first diffraction optical element have a refractive power in only the first direction, and the plurality of micro diffraction optical elements of said second diffraction optical element have a refractive power in only the second direction.
Claim 4
Dependent Claim 26 words
A system according to claim 1, further comprising a transparent substrate, on both surfaces of which, said first and second diffraction optical elements are respectively formed.
Claim 5
Dependent Claim 41 words
A system according to claim 1, further comprising: a first transparent substrate on one surface of which said first diffraction optical element is formed; and a second transparent substrate on one surface of which said second diffraction optical element is formed.
Claim 6
Dependent Claim 51 words
A system according to claim 1, wherein said first diffraction optical element is constituted by a plurality of diffraction optical elements arranged in a traveling direction of light, and said second diffraction optical element is constituted by a plurality of diffraction optical elements arranged in the traveling direction of the light.
Claim 7
Dependent Claim 74 words
A system according to claim 5, wherein the diffraction optical element, closest to the light source, of the plurality of diffraction optical elements constituting said first diffraction optical element is positioned to be conjugate with a surface to be irradiated, and the diffraction optical element, closest to the light source, of the plurality of diffraction optical elements constituting said second diffraction optical element is positioned to be conjugate with the surface to be irradiated.
Claim 8
Dependent Claim 186 words
A projection exposure apparatus comprising: a light source; an illumination optical system for guiding light supplied from said light source toward a reticle; and a projection optical system for projecting a pattern formed on the reticle onto a wafer, wherein said illumination optical system comprises: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and which have an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and which have an optical power different from the second optical power in the first direction, wherein light supplied from said light source forms a plurality of secondary light sources by passing through said first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated.
Claim 9
Dependent Claim 186 words
A projection exposure apparatus comprising: a light source; an illumination optical system for guiding light supplied from said light source toward a reticle; and a projection optical system for projecting a pattern formed on the reticle onto a wafer, wherein said illumination optical system comprises: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and which have an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and which have an optical power different from the second optical power in the first direction, wherein light supplied from said light source forms a plurality of secondary light sources by passing through said first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated.
Claim 10
Dependent Claim 52 words
An apparatus according to claim 7, wherein the plurality of micro diffraction optical elements of said first diffraction optical element have a refractive power in only said first direction, and the plurality of micro diffraction optical elements of said second diffraction optical element have a refractive power in only said second direction.
Claim 11
Dependent Claim 26 words
An apparatus according to claim 7, further comprising a transparent substrate, on both surfaces of which, said first and second diffraction optical elements are respectively formed.
Claim 12
Dependent Claim 41 words
An apparatus according to claim 7, further comprising: a first transparent substrate on one surface of which said first diffraction optical element is formed; and a second transparent substrate on one surface of which said second diffraction optical element is formed.
Claim 13
Dependent Claim 51 words
An apparatus according to claim 7, wherein said first diffraction optical element is constituted by a plurality of diffraction optical elements arranged in a traveling direction of light, and said second diffraction optical element is constituted by a plurality of diffraction optical elements arranged in the traveling direction of the light.
Claim 14
Dependent Claim 74 words
An apparatus according to claim 11, wherein a diffraction optical element, closest to said light source, of the plurality of diffraction optical elements constituting said first diffraction optical element is positioned to be conjugate with a surface to be irradiated, and a diffraction optical element, closest to said light source, of the plurality of diffraction optical elements constituting said second diffraction optical element is positioned to be conjugate with the surface to be irradiated.
Claim 15
Independent Claim 216 words
A device manufacturing method comprising the steps of: providing a projection exposure apparatus comprising: a light source; an illumination optical system for guiding light supplied from the light source toward a reticle; and a projection optical system for projecting a pattern formed on the reticle onto a wafer, wherein the illumination optical system comprises: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and which have an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and which have an optical power different from the second optical power in the first direction, wherein light supplied from the light source forms a plurality of secondary light sources by passing through the first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated; transferring a pattern formed on the reticle onto the wafer by exposure using the projection exposure apparatus; and developing the wafer.
Claim 16
Independent Claim 216 words
A device manufacturing method comprising the steps of: providing a projection exposure apparatus comprising: a light source; an illumination optical system for guiding light supplied from the light source toward a reticle; and a projection optical system for projecting a pattern formed on the reticle onto a wafer, wherein the illumination optical system comprises: a first diffraction optical element having a plurality of micro diffraction optical elements, which have a first optical power in a first direction and which have an optical power different from the first optical power in a second direction, perpendicular to the first direction; a second diffraction optical element having a plurality of micro diffraction optical elements, which have a second optical power in the second direction and which have an optical power different from the second optical power in the first direction, wherein light supplied from the light source forms a plurality of secondary light sources by passing through the first and second diffraction optical elements, and the first optical power is different from the second optical power; and a condenser lens, light from the secondary light sources passing through which generates Kohler illumination on a surface to be irradiated; transferring a pattern formed on the reticle onto the wafer by exposure using the projection exposure apparatus; and developing the wafer.
Claim 17
Dependent Claim 52 words
A method according to claim 13, wherein the plurality of micro diffraction optical elements of the first diffraction optical element have a refractive power in only the first direction, and the plurality of micro diffraction optical elements of the second diffraction optical element have a refractive power in only the second direction.
Claim 18
Dependent Claim 27 words
A method according to claim 13, further comprising providing a transparent substrate, on both surfaces of which, the first and second diffraction optical elements are respectively formed.
Claim 19
Dependent Claim 43 words
A method according to claim 13, further comprising: providing a first transparent substrate, on one surface of which, the first diffraction optical element is formed; and providing a second transparent substrate, on one surface of which, the second diffraction optical element is formed.
Claim 20
Dependent Claim 50 words
A method according to claim 13, wherein the first diffraction optical element is constituted by a plurality of diffraction optical elements arranged in a traveling direction of light, and the second diffraction optical element is constituted by a plurality of diffraction optical elements arranged in the traveling direction of light.
Claim 21
Dependent Claim 74 words
A method according to claim 13, wherein a diffraction optical element, closest to the light source, of the plurality of diffraction optical elements constituting the first diffraction optical element is positioned to be conjugate with a surface to be irradiated, and a diffraction optical element, closest to the light source, of the plurality of diffraction optical elements constituting the second diffraction optical element is positioned to be conjugate with the surface to be irradiated.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-07-19 2003-01-18 2003-07-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-07-19 2007-01-18 2007-07-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-07-19 2011-01-18 2011-07-20 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag