Characterization of Low-k Dielectric Etch Residue on the Sidewall by Chemical Force Microscope

Abstract

Atomic force microscope (AFM) with inclined sample measurement and hydrophobic functionalized AFM probe was used to visualize the sidewall of low-k pattern and allowed to characterize the hydrophobic characteristics on the sidewall after low-k etch. To functionalized the AFM probe, 1H,1H,2H,2H-Perfluorodecyltrichlorosilane (FDTS) as a hydrophobic film was coated on an AFM probe. Because of the magnitude of the phobic-phobic interaction force and the tip forced to make a phase shift. Using this technique the visualization and characterization of the etch residue on the low-k sidewall can be successfully performed. It is shown that the investigation toward an effective chemical clean for the etch residue removal could be applicable.