Experimental and DFT study of nitrogen atoms interactions with SiOCH low-κ films

Abstract

Damage of porous organosilicate glass (OSG) films with low dielectric constants (low-κ films) in plasma processing is a critical problem for modern microelectronics. For this problem, understanding and revealing of basic reaction steps for radicals etching and damage are of importance. Previously we have studied experimentally and theoretically the etching and damage of low-κ dielectric films under oxygen and fluorine atoms. Here the effects of N atoms on OSG films are studied experimentally by Fourier Transform InfraRed (FTIR) spectroscopy method and theoretically by density functional theory (DFT) method. Experimental FTIR spectra are compared with calculated vibrational spectra to reveal the relevant surface SiCH x N y groups which could be produced in multi-step reactive collisions of N atoms in ground and lower metastable states with OSG low-κ dielectric films.