Linewidth measurement on IC masks and wafers by grating test patterns
- 15 February 1980
- journal article
- Published by Optica Publishing Group in Applied Optics
- Vol. 19 (4), 525-533
- https://doi.org/10.1364/ao.19.000525
Abstract
Test patterns in the form of diffraction gratings are used for testing and monitoring linewidths on integrated circuit structures. The first and second diffraction orders produed by a laser beam are evaluated to give the width of the grating lines. Measurements on chrome masks show that this technique is accurate to 5% down to linewidths of 0.5 μm. The design of a test set for factory type mask testing is presented. Also, experiments are reported on the testing of patterns on Si wafers directly after. photoresist development and after various etching steps, and an automatic setup for rapid testing of wafers is described.This publication has 2 references indexed in Scilit:
- Rigorous diffraction theory for transmission phase gratings with deep rectangular groovesJournal of the Optical Society of America, 1978
- Linewidth measurement with an optical microscope: the effect of operating conditions on the image profileApplied Optics, 1977