Inventors:
Hans P. Kleinknecht - Bergdietikon, CH
Wolfram A. Bosenberg - Middlesex NJ
Assignee:
RCA Corporation - New York NY
International Classification:
G01N 2132
Abstract:
A method of optically testing the lateral dimensions of a pattern of material disposed on a substrate comprises applying the material to both the main area of the substrate and a test area on the same substrate, and selectively removing the material from both areas on the substrate simultaneously to form respectively the pattern on the main area and a diffraction grating on the test area. The diffraction grating is exposed to a beam of light, and the intensity of two of the diffracted beams is measured to obtain a ratio signal (I. sub. 2 /I. sub. 1), which is then utilized to determine the lateral dimensional tolerance of the integrated circuit pattern.