Method for Determining Thickness of Polymer Contamination on Silicon After CF4/H2
Original Publication Date: 1985-Aug-01
Included in the Prior Art Database: 2005-Feb-19
This article describes a method by which the amount of polymer deposition caused by CF4/H2 RIE (reactive ion etching) on Si can be measured accurately. Polymer contamination of Si surfaces in CF4/H2 RIE is a problem encountered in the manufacture of VLSI (very large-scale integration) devices e.g., in the opening of contact holes. Therefore, no simple method was available to quantify the degree of contamination, e.g., the thickness of the polymeric contamination. Such a simple method is described herein by which it is possible to quantify the thickness of CF4/H2-induced polymer layers very accurately. The method is based on ellipsometry, using a HeNe laser as a light source.