Adaptive control of photolithography

Oscar D. Crisalle; Robert A. Soper; Duncan A. Mellichamp; Dale E. Seborg

doi:10.1117/12.44462

1 July 1991 Adaptive control of photolithography

Oscar D. Crisalle, Robert A. Soper, Duncan A. Mellichamp, Dale E. Seborg

Proceedings Volume 1464, Integrated Circuit Metrology, Inspection, and Process Control V; (1991) https://doi.org/10.1117/12.44462
Event: Microlithography, 1991, San Jose, CA, United States

Abstract

Adaptive control techniques, with their capability for providing satisfactory control even when the process changes with time, are promising candidates for dealing with common problems encountered in photolithography processing such as batch-to-batch variations in resist properties, inconsistencies in resist curing, etc. In this paper an adaptive control strategy for the photolithography process is proposed and evaluated. The design utilizes a reduced-order lithography model, an on-line parameter estimator, and a nonlinear model-inversion controller (NMIC). The width of the printed resist lines--a crucial output of photolithography--is controlled by automatically adjusting the exposure energy. In the calculation of the appropriate exposure adjustment, the controller uses both measured critical dimensions as well as estimated values produced by the process model. The control system is capable of tracking changes in the photolithography process by automatic updating of key model parameters as the process evolves in time. Simulation studies of the closed-loop adaptive control strategy using the PROLITH simulation package to represent the lithography process demonstrate the feasibility of this approach.

Citation Download Citation

Oscar D. Crisalle, Robert A. Soper, Duncan A. Mellichamp, and Dale E. Seborg "Adaptive control of photolithography", Proc. SPIE 1464, Integrated Circuit Metrology, Inspection, and Process Control V, (1 July 1991); https://doi.org/10.1117/12.44462

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available