Cleanup method for optics in immersion lithography

• US 20070171390A1
• Filed: 02/08/2007
• Published: 07/26/2007
• Est. Priority Date: 04/11/2003
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Watson, Douglas, Kawai, Hidemi, Novak, W., Hazelton, Andrew
• Application Number:
  US11/703,802
• Publication Number:
  US 20070171390A1
• Time in Patent Office: Days
• US Class Current: 355/30
• CPC Class Codes: B08B 3/04 Cleaning involving contact with liquid
• CPC Class Codes: B08B 3/12 by sonic or ultrasonic vibrations washing or rinsing machines for crockery or tableware using sonic or ultrasonic waves A47L15/13; of natural teeth, of prostheses using ultrasonic techniques similar to those used for natural teeth A61C17/20; application of ultrasonic vibrations to chemical, physical or physico-chemical processes in general B01J19/10
• CPC Class Codes: G03F 7/70341 Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply chemical composition of immersion liquids G03F7/2041
• CPC Class Codes: G03F 7/70891 Temperature
• CPC Class Codes: G03F 7/70916 Pollution mitigation, i.e. mitigating effect of contamination or debris, e.g. foil traps
• CPC Class Codes: G03F 7/70925 Cleaning, i.e. actively freeing apparatus from pollutants, e.g. using plasma cleaning

Abstract

A lens cleaning module is provided for a lithography system having an exposure apparatus including an objective lens. The system includes a scanning stage for supporting a wafer beneath the objective lens. A cleaning module coupling with the lithography system is provided for cleaning the objective lens in a non-manual cleaning process.

Claims

1. A lens cleaning module for a lithography system having an exposure apparatus including an objective lens, comprising:

a scanning stage for supporting a wafer beneath the objective lens; and

a cleaning module coupling with said lithography system is provided for cleaning the objective lens in a non-manual cleaning process.

4. The lens-cleaning module of claim 1, wherein the cleaning module includes a heating/drying module for drying the objective lens.

5. The lens cleaning module of claim 1, wherein said lithography system is an immersion lithography apparatus.

6. The lens-cleaning module of claim 1, wherein said exposure apparatus has a light source which emits light having a wavelength of less than about 250 nm.

8. The lens-cleaning module of claim 1, wherein said cleaning module comprises a fluid retaining wall carried by said scanning stage and a cleaning fluid provided on said scanning stage and retained by said fluid retaining wall for contacting the objective lens.

9. The lens-cleaning module of claim 1, wherein said cleaning fluid is ethanol.

11. The lens-cleaning module of claim 8, further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during operation.

2-3. -3. (canceled)

7. (canceled)

10. (canceled)

12. (canceled)

13. A method for patterning semiconductor wafers by immersion lithography to improve exposure quality comprising the steps of:

loading a semiconductor wafer on a stage of an immersion lithography apparatus;

filling a liquid between said wafer and an objective lens of said immersion lithography apparatus;

exposing said semiconductor wafer to a light source having a wavelength of less than about 250 nm;

unloading said semiconductor wafer;

cleaning a surface of said objective lens after said exposure step utilizing a non-manual lens cleaning module.

16. The method for patterning semiconductor wafer by immersion lithography according to claim 13, wherein said non-manual lens cleaning module further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during cleaning operation.

14-15. -15. (canceled)

17. A method for patterning semiconductor wafers by immersion lithography to improve exposure quality comprising the steps of:

utilizing a non-manual lens cleaning module to clean the surface of objective lens before water exposure processing;

loading a semiconductor wafer on a stage of an immersion lithography apparatus;

filling a liquid between said wafer and an objective lens of said immersion lithography apparatus;

exposing said semiconductor wafer to a light source having a wavelength of less than about 250 nm.

20. The method for patterning semiconductor wafer by immersion lithography according to claim 17, wherein said non-manual lens cleaning module further comprising a contact material for cleaning and cleaning fluid is distributed between contact material and lens during cleaning operation.

18-19. -19. (canceled)