Production of integrated circuits necessitates inspection of masks, chips, and wafers to guarantee yield and quality. This paper presents a simple, low cost mask inspection system. The system differs from the commercially available mask inspection systems in an important way. Our system is based on an IBM compatible PC, and provides a simple and cost effective solution for the application described. The hardware and software of the system have been modularized with the objective to make the system more versatile and reconfigurable. The basic system can easily be coupled with various front ends. Thus, with slight modifications in the software, the system can be used to pursue other applications as well. The inspection algorithms make use of reference comparison and feature extraction approaches for guaranteed defect detection. The defects detected are further analyzed for extraction of characteristic features like location, dimensions, and type to create a diagnostic report at the end of inspection. The defect data in the report can be used for online mask repair. Preliminary experiments with the system have shown promising results. The configuration of the system along with the image processing algorithms used are detailed. The paper ends with a brief discussion on the results obtained.

Date Published: 1 November 1992
PDF: 8 pages
Proc. SPIE 1823, Machine Vision Applications, Architectures, and Systems Integration, (1 November 1992); doi: 10.1117/12.132091

Published in SPIE Proceedings Vol. 1823:
Machine Vision Applications, Architectures, and Systems Integration
Bruce G. Batchelor; Susan Snell Solomon; Frederick M. Waltz, Editor(s)