Process for detection of sub-micron particulate contamination on a bare (planar) substrate

Abstract

Particular contamination below about 0.3 microns in average diameter on an IC wafer substrate is detected by forming a film of a volatile liquid on the wafer's surface and observing interference patterns formed by particles during the evaporation process. These interference patterns magnify the "effective" particle size many times, making detection through an optical microscope possible.