Exposure method and apparatus, and method for fabricating device with light amount distribution having light larger in first and second pairs of areas

• US 20090185156A1
• Filed: 03/12/2009
• Published: 07/23/2009
• Est. Priority Date: 04/09/2003
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Hirukawa, Shigeru, Kudo, Takehito
• Granted Patent: US 9,146,474 B2
• Time in Patent Office: Days
• US Class Current: 355/71
• CPC Class Codes: G03B 27/42 for automatic sequential copying of the same original G03B27/34, G03B27/53 take precedence
• CPC Class Codes: G03F 7/70091 Illumination settings, i.e. intensity distribution in the pupil plane or angular distribution in the field plane; On-axis or off-axis settings, e.g. annular, dipole or quadrupole settings; Partial coherence control, i.e. sigma or numerical aperture [NA]
• CPC Class Codes: G03F 7/701 Off-axis setting using an aperture
• CPC Class Codes: G03F 7/70108 Off-axis setting using a light-guiding element, e.g. diffractive optical elements [DOEs] or light guides
• CPC Class Codes: G03F 7/70158 Diffractive optical elements
• CPC Class Codes: G03F 7/70191 Optical correction elements, filters or phase plates for controlling intensity, wavelength, polarisation, phase or the like
• CPC Class Codes: G03F 7/70566 Polarisation control

Abstract

An exposure method and apparatus simultaneously transfer patterns with various pitches with high-resolution. On the pupil surface of an illumination system, at least first and second pairs of areas are set. The distribution of intensity of light over the pupil surface is set so that the intensities of light of the second pair of areas is smaller than that of the first pair of areas.

Claims

1. An exposure method for illuminating a pattern with an illumination system to expose a substrate through a projection system,

wherein the pattern is illuminated with illumination light having a light amount distribution, which is set such that an amount of light is larger in an on-axis area substantially including an optical axis and in a plurality of off-axis areas arranged out of the optical axis than in an area other than the on-axis area and the plurality of off-axis areas on a pupil plane of the illumination system, polarization states of the illumination light being different between the on-axis area and the off-axis areas.

2. An exposure method according to claim 1, wherein

the illumination light distributed in the off-axis areas is substantially linearly polarized light.

3. An exposure method according to claim 2, wherein

a direction of the linearly polarized light approximately coincides with a tangent direction.

4. An exposure method according to claim 2, wherein

a direction of the linearly polarized light approximately coincides with a longitudinal direction of the off-axis areas.

5. An exposure method according to claim 2, wherein

the illumination light distributed in the on-axis area is substantially non-linearly polarized light.

6. An exposure method according to claim 5, wherein

the illumination light distributed in the on-axis area is substantially non-polarized light.

7. An exposure method according to claim 2, wherein

the illumination light distributed in the on-axis area and the illumination light distributed in the off-axis areas are linearly polarized and have substantially different polarization directions.

8. An exposure method according to claim 1, wherein

the plurality of off-axis areas include an even number of areas at approximately a same distance from the optical axis.

9. An exposure method according to claim 1, wherein

the on-axis area and the plurality of off-axis areas are arranged on a same straight line passing through the optical axis.

10. The device manufacturing method, comprising:

exposing a substrate by the exposure method as recited in claim 1;

developing the exposed substrate; and

processing the developed substrate.

11. An exposure apparatus, comprising:

an illumination system which illuminates a pattern; and

a projection system which projects the pattern onto a substrate, wherein the exposure apparatus comprises;

a formation optical system which can change a light amount distribution of illumination light on a pupil plane of the illumination system, which can generate a light amount distribution in which an amount of light is larger in an on-axis area substantially including an optical axis and in a plurality of off-axis areas arranged out of the optical axis than in an area other than the on-axis area and the plurality of off-axis areas on the pupil plane, and which makes polarized states of the illumination light differ between the on-axis area and the off-axis areas.

12. An exposure apparatus according to claim 11, wherein

the illumination light distributed in the off-axis areas is substantially linearly polarized light.

13. An exposure apparatus according to claim 12, wherein

a direction of the linearly polarized light approximately coincides with a tangent direction.

14. An exposure apparatus according to claim 12, wherein

a direction of the linearly polarized light approximately coincides with a longitudinal direction of the off-axis areas.

15. An exposure apparatus according to claim 12, wherein

the illumination light distributed in the on-axis area is substantially non-linearly polarized light.

16. An exposure apparatus according to claim 15, wherein

the illumination light distributed in the on-axis area is substantially non-polarized light.

17. An exposure apparatus according to claim 12, wherein

the illumination light distributed in the on-axis area and the illumination light distributed in the off-axis areas are substantially linearly polarized and have different polarization directions.

18. An exposure apparatus according to claim 11, wherein

the plurality of off-axis areas include an even number of areas at approximately a same distance from the optical axis.

19. An exposure apparatus according to claim 11, wherein

the on-axis area and the plurality of off-axis areas are arranged on a same straight line passing through the optical axis.

20. An exposure apparatus according to claim 11, wherein

the formation optical system can change the light amount distribution by movement of an optical element and/or by exchange of optical elements.

21. A device manufacturing method, comprising:

exposing a substrate with the exposure apparatus as recited in claim 11;

developing the exposed substrate; and

processing the developed substrate.