Exposure apparatus, device manufacturing method, pattern generator and maintenance method

• US 20050237375A1
• Filed: 04/21/2005
• Published: 10/27/2005
• Est. Priority Date: 04/21/2004
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Nakamura, Takashi, Tokita, Toshinobu, Ota, Hirohisa, Kasumi, Kazuyuki, Kawakami, Eigo
• Granted Patent: US 7,233,383 B2
• Time in Patent Office: Days
• US Class Current: 347/224
• 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 7/70691 Handling of masks or workpieces
• CPC Class Codes: G03F 7/70916 Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps

Abstract

An exposure apparatus for exposing a predetermined pattern onto an object via a projection optical system includes a pattern generating unit that includes plural pixels, and generates the predetermined pattern by driving the plural pixels, a measuring unit for measuring at least one of optical performance of the pattern generating unit and a driving state of the plural pixels, and a maintenance unit for maintaining the pattern generating unit based on a measuring result by the measuring unit.

Claims

1. An exposure apparatus comprising:

a projection optical system for projecting a predetermined pattern onto an object to be exposed;

a pattern generating unit that includes plural pixels, and generates the predetermined pattern by driving the plural pixels;

a measuring unit for measuring at least one of optical performance of said pattern generating unit and a driving state of the plural pixels; and

a maintenance unit for maintaining said pattern generating unit based on a measuring result by said measuring unit.

2. An exposure apparatus according to claim 1, wherein said measuring unit measures reflectance or transmittance of the plural pixels.

3. An exposure apparatus according to claim 1, wherein said maintenance unit includes:

a removing unit for removing foreign matters from the plural pixels; and

an exchanging unit for exchanging the pattern generating unit.

4. An exposure apparatus according to claim 3, wherein said removing unit includes at least one of an ultrasonic irradiating member for irradiating ultrasonic waves onto the plural pixels, a liquid dropping member for dropping cleansing agent, and a gas injecting member for injecting dry gas.

5. An exposure apparatus according to claim 3, wherein said exchanging unit includes:

a transporting unit for transporting said pattern generating unit; and

a cassette for housing said pattern generating unit when the transporting unit transports said pattern generating unit.

6. An exposure apparatus according to claim 1, further comprising a stage for supporting said pattern generating unit, said stage including a positioning mechanism for positioning said pattern generating unit.

7. An exposure apparatus according to claim 1, wherein the plural pixels form a mirror, and said pattern generating unit includes a spring or latch mechanism for driving the mirror.

10. A device manufacturing method comprising the steps of:

exposing an object using the exposure apparatus according to claim 1;

and

developing the object that has been exposed.

8. An exposure apparatus comprising:

a projection optical system for projecting a predetermined pattern onto an object to be exposed,

a pattern generating unit that includes plural pixels, and generates the predetermined pattern by driving the plural pixels;

an obtaining unit for obtaining a positional relationship between a position of the predetermined pattern and a position of the object; and

a driving unit for driving, based on the positional relationship obtained by said obtaining unit, at least one of a first stage for supporting said pattern generating unit and a second stage for supporting the object.

9. An exposure apparatus according to claim 8, wherein said pattern generating unit generates the predetermined pattern without using a deteriorated pixel among the plural pixels.

11. A device manufacturing method comprising the steps of:

exposing an object using the exposure apparatus according to claim 8;

and

developing the object that has been exposed.

12. A pattern generator comprising:

a pattern generating unit that includes plural pixels, and generates a predetermined pattern by driving the plural pixels;

a measuring unit for measuring at least one of optical performance of said pattern generating unit and a driving state of the plural pixels; and

a maintenance unit for maintaining said pattern generating unit based on a measuring result by said measuring unit.

13. A maintenance method for a pattern generator that includes a pattern generating unit that includes plural pixels, and generates a predetermined pattern by driving the plural pixels, said maintenance method comprising the steps of:

obtaining one or more of an optical performance of said pattern generating unit and a driving state of the plural pixels; and

determining, based on information obtained by said obtaining step, whether the plural pixels deteriorate; and

maintaining the pattern generating unit based on a determination by said determining step.

14. A maintenance method according to claim 13, wherein said determining step determines that the plural pixels deteriorate when a changing amount of the optical performance of the pixels is outside a permissible range, when a driving stroke of the pixels is outside a permissible range, or when the cumulative driving times of the pixels exceeds a predetermined value.

15. A maintenance method according to claim 13, wherein said maintaining step includes the steps of:

recovering a deteriorated pixel; and

exchanging the pattern generating unit.

16. A maintenance method according to claim 13, wherein said determining step determines that the plural pixels deteriorate when a changing amount of the optical performance of the pixels is outside a permissible range, and further determines whether the cumulative deterioration times is equal to or greater than a predetermined value, and

wherein said maintaining step exchanges the pattern generating unit when the cumulative deterioration time is equal to or greater than the predetermined value, and recovers the optical performance of the pixels when the cumulative driving time of the pixels is below the predetermined value.

17. A maintenance method according to claim 14, wherein said maintaining step exchanges the pattern generating unit both when the changing amount of the optical performance of the pixels is outside the permissible range and when the driving state of the pixels is outside the permissible range.

18. A maintenance method for a pattern generator that includes a pattern generating unit that includes plural pixels, and generates a predetermined pattern by driving the plural pixels, said maintenance method comprising:

an obtaining step of obtaining at least one of optical performance of said pattern generating unit and a driving state of the plural pixels;

a first determining step of determining, based on information obtained by said obtaining step, whether the optical performance of the plural pixels deteriorates;

a second determining step of determining whether the number of determinations of deterioration is equal to or greater than a predetermined value when said first determining step determines that the optical performance deteriorates; and

a step of exchanging the pattern generating unit when said second determining step determines that the number of determinations exceeds the predetermined value, and of recovering the optical performance of the pixels when said second determining step determines that the number of determinations is smaller than the predetermined value.

19. A maintenance method according to claim 18, further comprising:

a third determining step of determining whether a driving state of the plural pixels deteriorates, when said first determining step determines that the optical performance does not deteriorate; and

an exchanging step of exchanging the pattern generating unit when said third determining step determines that the driving state deteriorates.