A control system for photolithographic sequences

Author

Leang, Sovarong ; Ma, Shang-Yi ; Thomson, John ; Bombay, Bart John ; Spanos, Costas J.

Author_Institution

California Univ., Berkeley, CA, USA

Volume

9

Issue

2

fYear

1996

fDate

5/1/1996 12:00:00 AM

Firstpage

191

Lastpage

207

Abstract

The goal of our control system is to improve the reliability, accuracy, and economy of operation of a sequence of interrelated processes. We achieve this task by using well known, rigorous statistical techniques to continuously monitor process parameters, detect out-of-control equipment, and then optimally adjust relevant machine inputs to bring the process back on target We have implemented the supervisory control system on the photolithography sequence in the Berkeley Microfabrication Laboratory, where it has been conclusively proven that the supervisory control system increases significantly the capability of the entire process. The supervisory control algorithms, consisting of feedback and feed-forward control, multivariate, model-based statistical process control (SPC), and automated specification management algorithms, are independent of machine and/or process, and can be applied to any semiconductor manufacturing sequence

Keywords

feedforward; integrated circuit yield; photolithography; process control; statistical process control; automated specification management algorithms; feed-forward control; feedback control; interrelated processes; machine inputs; photolithographic sequences; process parameter monitoring; rigorous statistical techniques; semiconductor manufacturing sequence; statistical process control; supervisory control system; Automatic control; Condition monitoring; Control systems; Feedback; Feedforward systems; Laboratories; Lithography; Manufacturing automation; Process control; Supervisory control;

fLanguage

English

Journal_Title

Semiconductor Manufacturing, IEEE Transactions on

Publisher

ieee

ISSN

0894-6507

Type

jour

DOI

10.1109/66.492813

Filename

492813