PHOTOMASK HAZE REDUCTION VIA VENTILATION

• US 20080266534A1
• Filed: 04/25/2007
• Published: 10/30/2008
• Est. Priority Date: 04/25/2007
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Inventors: Yoo, Chue San
• Granted Patent: US 7,839,480 B2
• Time in Patent Office: Days
• US Class Current: 355/30
• CPC Class Codes: G03F 1/64 characterised by the frames, e.g. structure or material, including bonding means therefor

Abstract

Where a framed pellicle is mounted on a photomask, the framed pellicle comprises a pellicle frame and a pellicle membrane coupled to the pellicle frame, the pellicle frame has first and second apertures each communicating a first space surrounded by the photomask and the framed pellicle with a second space outside of the framed pellicle, exposing a photoresist layer formed on a substrate by flowing gas from within the first space to outside the framed pellicle through the first aperture while simultaneously exposing the photoresist layer to ultraviolet light through the pellicle membrane and the photomask.

Claims

1. A method of exposing a photoresist layer on a substrate surface to ultraviolet light through a photomask, comprising:

mounting a framed pellicle on the photomask, the framed pellicle comprising a pellicle frame and a pellicle membrane coupled to the pellicle frame, the pellicle frame having first and second apertures each communicating a first space surrounded by the photomask and the framed pellicle with a second space outside of the framed pellicle; and

flowing gas from within the first space through the first aperture to outside the framed pellicle while simultaneously exposing the photoresist layer to ultraviolet light through the pellicle membrane and the photomask.

2. The method of claim 1 wherein flowing gas from the first space through the first aperture to outside the framed pellicle comprises communicating a positive pressure gas source with the second aperture.

3. The method of claim 1 wherein flowing gas from the first space through the first aperture to outside the framed pellicle comprises communicating a vacuum source with the first aperture.

4. The method of claim 1 wherein flowing gas from the first space through the first aperture to outside the framed pellicle comprises communicating a positive pressure gas source with the second aperture and communicating a vacuum source with the first aperture.

5. The method of claim 1 wherein flowing gas from the first space through the first aperture to outside the framed pellicle comprises communicating a positive pressure gas source with a tube external to the framed pellicle and having an opening proximate the first aperture such that gas flow within the tube creates a suction force urging gas from the first space through the first aperture and the opening and into the tube.

6. An exposure apparatus, comprising:

a chamber configured to accommodate a substrate and a photomask, wherein the substrate includes a photoresist layer located thereon, the photomask includes a framed pellicle mounted thereon, the framed pellicle includes a pellicle frame and a pellicle membrane coupled to the pellicle frame, and the pellicle frame includes first and second apertures each communicating a first space surrounded by the photomask and the framed pellicle with a second space outside of the framed pellicle;

an imager configured to direct an exposure light through the pellicle membrane and the photomask and onto the photoresist layer; and

a ventilator configured to direct gas flow from within the first space to outside the framed pellicle through the first aperture while the imager simultaneously directs the exposure light through the pellicle membrane and photomask and onto the photoresist layer.

7. The exposure apparatus of claim 6 wherein the ventilator includes a positive pressure gas source in fluidic communication with the first aperture.

8. The exposure apparatus of claim 6 wherein the ventilator includes a vacuum source in fluidic communication with the second aperture.

9. The exposure apparatus of claim 6 wherein the ventilator includes a positive pressure gas source in fluidic communication with the first aperture and a vacuum source in fluidic communication with the second aperture.

10. The exposure apparatus of claim 6 further comprising a receptacle configured to receive the substrate.

11. The exposure apparatus of claim 6 further comprising a receptacle configured to receive the photomask.

12. The exposure apparatus of claim 6 wherein the ventilator includes a receptacle configured to align at least one of the photomask and the framed pellicle relative to the substrate.

13. The exposure apparatus of claim 6 wherein the ventilator includes a filter configured to filter gas flowing between the first and second spaces.

14. A ventilator for use with an exposure apparatus having a chamber and an imager, wherein the chamber is configured to accommodate a substrate and a photomask, the substrate includes a photoresist layer located thereon, the photomask includes a framed pellicle mounted thereon, the framed pellicle includes a pellicle frame and a pellicle membrane coupled to the pellicle frame, the pellicle frame includes first and second apertures each communicating a first space surrounded by the photomask and the framed pellicle with a second space outside of the framed pellicle, and the imager is configured to direct an exposure light through the pellicle membrane and the photomask and onto the photoresist layer, the ventilator comprising:

means for directing gas flow from within the first space to outside the framed pellicle through the first aperture while the imager simultaneously directs the exposure light through the pellicle membrane and the photomask and onto the photoresist layer.

15. The ventilator of claim 14 wherein the gas flow directing means includes a positive pressure gas source configured to fluidicly communicate with the first aperture.

16. The ventilator of claim 14 wherein the gas flow directing means includes a vacuum source configured to fluidicly communicate with the second aperture.

17. The ventilator of claim 14 wherein the gas flow directing means includes a positive pressure gas source configured to fluidicly communicate with the first aperture and a vacuum source configured to fluidicly communicate with the second aperture.

18. The ventilator of claim 14 further comprising a receptacle configured to receive at least one of the substrate and the photomask.

19. The ventilator of claim 14 further comprising a receptacle configured to orient at least one of the photomask and the framed pellicle relative to the substrate.

20. The ventilator of claim 14 wherein the gas flow directing means comprises means for filtering gas flowing between the first and second spaces.