Lithographic apparatus and device manufacturing method

• US 20050286035A1
• Filed: 06/28/2004
• Published: 12/29/2005
• Est. Priority Date: 06/28/2004
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Van Der Mast, Karel Diederick, Troost, Kars Zeger
• Granted Patent: US 7,116,403 B2
• Time in Patent Office: Days
• US Class Current: 355/67
• CPC Class Codes: G03F 7/70225 Optical aspects of catadioptric systems, i.e. comprising reflective and refractive elements
• CPC Class Codes: G03F 7/70291 Addressable masks, e.g. spatial light modulators [SLMs], digital micro-mirror devices [DMDs] or liquid crystal display [LCD] patterning devices
• CPC Class Codes: G03F 7/70425 Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning

Abstract

Lithographic apparatus providing a patterned beam of radiation in which radiation that is linearly polarized in a first direction has a first pattern and radiation that is linearly polarized in an orthogonal direction has a second pattern.

Claims

1. A lithographic apparatus comprising:

an illumination system that supplies a beam of radiation;

a beam splitter that splits the beam into first and second beams of radiation;

a first array of individually controllable elements that patterns the first beam with a first pattern;

a second array of individually controllable elements that patterns the second beam with a second pattern;

a beam combiner that combines the first and second patterned beams to form a combined patterned beam; and

a system that projects the combined patterned beam onto a target portion of a substrate,

wherein a first portion of the combined patterned beam derived from the first patterned beam is substantially linearly polarized, and

wherein a second portion of the combined patterned beam derived from the second patterned beam is substantially linearly polarized, substantially orthogonal to the first portion.

2. The lithographic apparatus of claim 1, wherein:

the first and second portions of the combined patterned beam are projected onto the substrate at respective oblique angles; and

an illumination field of at least one of the first and second portions of the combined patterned beam of radiation substantially lies in a plane that is perpendicular to a plane that is defined by a line along which the respective beam of radiation is projected onto the substrate and a line perpendicular to the substrate.

3. The lithographic apparatus of claim 1, wherein a single optical element is used as both the beam splitter and the beam combiner.

4. The lithographic apparatus of claim 1, wherein:

the beam splitter is a polarizing cube;

said first beam of radiation being derived from radiation in the beam of radiation that is linearly polarized in a first direction; and

said second beam of radiation being derived from radiation in the beam of radiation that is linearly polarized in a second direction that is orthogonal to the first direction.

5. The lithographic apparatus of claim 4, further comprising:

a quarter wavelength plate located in a beam path of at least one of the first and second beams of radiation between the polarizing cube and a respective one of the first and second arrays of individually controllable elements.

6. The lithographic apparatus of claim 1, wherein the system preserves the polarization of the first and second portions of the combined patterned beam.

7. The lithographic apparatus of claim 6, wherein the system provides independent correction of chromatic errors in each of the first and second portions of the combined patterned beam.

8. The lithographic apparatus of claim 1, wherein the beam of radiation from illumination system comprises:

radiation in a first portion of a pupil plane that is substantially linearly polarized; and

radiation in a second portion of the pupil plane is substantially linearly polarized and substantially orthogonal to the radiation in the first portion of the pupil plane.

9. The lithographic apparatus according to claim 1, wherein the beam of radiation from illumination system comprises:

radiation in opposite quadrants of an illumination field in a pupil plane is substantially linearly polarized in substantially parallel directions; and

radiation in adjacent quadrants of the illumination field in the pupil plane is substantially linearly polarized in substantially orthogonal directions.

10. A lithographic apparatus, comprising:

an illumination system that supplies a beam of radiation;

a patterning device that patterns the beam;

a system that projects the patterned beam onto a target portion of a substrate, the system comprises

a polarizing cube that separates the patterned beam into a first patterned sub-beam having radiation that is substantially linearly polarized in a first direction and second patterned sub-beam having radiation that is substantially linearly polarized in a second direction, which is substantially orthogonal to the first direction;

first and second optical correction units that correct the first and second patterned sub-beams, respectively; and

a beam combiner that combines the first and second corrected sub-beams to form a corrected patterned beam.

11. The lithographic apparatus of claim 10, wherein the system preserves the polarization of the patterned beam.

12. The lithographic apparatus of claim 10, wherein:

the beam combiner is the polarizing cube; and

the optical correction units return the corrected sub-beams along a reverse of an optical path of the patterned sub-beams.

13. The lithographic apparatus of claim 12, further comprising:

a first quarter wavelength plate positioned in an optical path of the first patterned sub-beam and the first corrected sub-beam between the polarizing cube and the first optical correction unit; and

a second quarter wavelength plate positioned in the optical path of the second patterned beam and the second corrected sub-beam between the polarizing cube and the second optical correction unit.

14. A device manufacturing method, comprising:

(a) splitting a beam of radiation into first and second beams of radiation using a beam splitter;

(d) pattering the first beam of radiation with a first pattern using a first array of individually controllable elements;

(e) pattering the second beam of radiation with a second pattern using a second array of individually controllable elements;

(f) combining the first and second patterned beams to form a combined patterned beam using a beam combiner; and

(g) projecting the combined patterned beam of radiation onto a target portion of a substrate,

wherein a first portion of the combined patterned beam derived from the first patterned beam is substantially linearly polarized,

wherein a second portion of the combined patterned beam derived from the second patterned beam is substantially linearly polarized, substantially orthogonal to the first portion.

15. A device manufacturing method comprising:

(a) patterning a beam of radiation using a patterning device;

(b) projecting the patterned beam onto a target portion of a substrate;

(c) separating the projected patterned beam into a first patterned sub-beam having radiation that is substantially linearly polarized in a first direction using a polarized cube;

(d) separating the projected patterned beam into a second patterned sub-beam having radiation that is substantially linearly polarized in a second direction, substantially orthogonal to the first direction using the polarized cube

(e) correcting each of the first and second patterned sub-beams using respective first and second optical correction units; and

(f) combining the first and second corrected sub-beams to form a corrected patterned beam.