Claims
- 1. A photolithography system for processing at least one semiconductor wafer having a photoresist layer thereon, said system having a set of control parameters, said system comprising:
- positioning means for positioning said wafers within said system;
- exposing means for exposing said photoresist to light and printing at least one mask pattern on said photoresist;
- a phase contrast microscope positioned to measure linewidth characteristics of latent images of said at least one mask pattern on said photoresist of said wafer prior to developing said photoresist; and
- adjustment means for adjusting said control parameters according to said measured linewidth characteristics of said latent images.
- 2. A system as recited in claim 1 further comprising development means for developing said photoresist layer.
- 3. A system as recited in claim 1 wherein said initial set of control parameters includes exposure time and wherein said adjusting means changes said exposure time.
- 4. A system as recited in claim 1 wherein said initial set of control parameters includes the position of said wafer within said photolithography system and wherein said adjusting means changes said position of said wafer.
- 5. A method as recited in claim 1 wherein said initial set of control parameters includes the defocus of said photolithography system and wherein said adjusting means changes said defocus of said photolithography system.
- 6. A method as recited in claim 1 wherein said initial set of control parameters includes the numerical aperture of said photolithography system and wherein said adjusting means changes said numerical aperture of said photolithography system.
- 7. A method as recited in claim 1 wherein said initial set of control parameters includes the illumination coherence of said photolithography system and wherein said adjusting means changes said illumination coherence of said photolithography system.
Parent Case Info
This application is a divisional continuation of application Ser. No. 07/846,590, filed Mar. 5, 1992, now U.S. Pat. No. 5,283,141.
US Referenced Citations (5)
Non-Patent Literature Citations (3)
Entry |
K. C. Hickmn; "Use Of Diffracted Light From Latent Images To Improve Lithography Control"; SPIE Microlithography Conference; 1464-22, Mar. 5, 1991. |
Thomas E. Adams; "Applications of Latent Image Metrology In Microlithography"; SPIE Microlithography Conference; 1464-26; Mar. 5, 1991. |
Karl W. Edmark et al.; "Stepper Overlay Calibration Using Alignment To A Latent Image"; SPIE vol. 538; Optical Microlithography IV; pp. 91-101 (1985). |
Divisions (1)
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Number |
Date |
Country |
Parent |
846590 |
Mar 1992 |
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