Kla-tencor Technologies Corporation

Christopher M Pohlhammer

Shankar Krishnan

Gary Janik

Liang-Guo Wang

Michael P Green

A method for measuring a characteristic of a substrate, including directing an incident beam at an inspection grid of points on the substrate, receiving the reflected beam with a position sensitive detector, measuring the displacement of the reflected beam from its expected location, compiling a database of the displacement measurements, examining the database for effects of a pattern induced anomaly in the displacement measurements, producing an adjusted database, and deriving the characteristic of the substrate from the adjusted database. Thus, pattern induced errors from the displacement measurements are corrected. In this manner, problems with interpreting the reflection angles of a beam in substrate stress analysis equipment are overcome where distortions in the reflection angles are caused by deposition patterns on the substrates.

Patterned substrate surface mapping

An apparatus for measuring a thickness of a substrate having an upper surface, without contacting the upper surface of the substrate. A platen having a base surface receives the substrate, and a reference surface is disposed at a known first height from the platen surface. A non contact sensor senses the known first height of the reference surface without making physical contact with the reference surface. The non contact sensor further senses a relative difference between the known first height of the reference surface and a second height of the upper surface of the substrate without making physical contact with the upper surface of the substrate. A controller controls the sensor and determines the thickness of the substrate based at least in part on the known first height of the reference surface and the relative difference between the known first height of the reference surface and the second height of the upper surface of the substrate.

Growing community of inventors

San Ramon, CA, United States of America

Christopher M Pohlhammer