CPC H01J 37/32972 (2013.01) [H01J 37/32449 (2013.01); H01J 37/32963 (2013.01); H01L 21/67253 (2013.01); H01L 22/26 (2013.01); G01N 21/00 (2013.01); H01J 37/32458 (2013.01); H01J 2237/3345 (2013.01)] | 10 Claims |
1. An apparatus for in-situ etch process monitoring in a plasma processing chamber, the apparatus comprising:
a continuous wave broadband light source;
an illumination system configured to illuminate an area on a substrate with an incident light beam being directed from the continuous wave broadband light source at normal incidence to the substrate;
a collection system configured to collect a reflected light beam being reflected from the illuminated area on the substrate, and to direct the reflected light beam to a first light detector; and
a controller configured to determine a property of the substrate or structures formed thereupon based on a reference light beam and the reflected light beam, and control an etch process based on the determined property,
wherein the reference light beam is generated by the illumination system by splitting a portion of the incident light beam through a beam splitter or using a mirror, thereafter directing the reference light beam to a second light detector.
|