Characteristics of low-kappa SiOC films deposited via atomic layer deposition

Abstract

The deposition of SiOC thin films via remote plasma atomic layer deposition was investigated. Octamethylcyclotetrasiloxane (OMCTS) and O-2, Ar, H-2 plasmas were respectively used as a precursor and reactants during the deposition process at 400 degrees C. Plasma and deposition temperatures had a significant effect on the physical and electrical characteristics of the films. When Ar and H-2 plasma was respectively used during the deposition process, films exhibited low dielectric constants while incorporating carbon; however, O-2 plasma yielded carbon free SiO2 films. Low dielectric constants resulted in low film densities and the presence of carbon within the films. When Ar and H-2 plasma was used as the reactant gas, pores within the films with loose structures and SieC bonds served to lower the dielectric constant. As a result, Ar and H-2 plasma conditions exhibited low dielectric constants of 2.7 and 3.1 at 100 degrees C, respectively. Meanwhile, the presence of carbon and low film densities caused leakage paths within the films. X-ray photoelectron spectroscopy supported analyses demonstrating the bonding characteristics of Si, C, O components.