Electron spin resonance analysis of sputtering-induced defects in advanced low-κ insulators (κ=2.0–2.5)

[Display omitted] •We have carried out a low-temperature ESR study of damage induced by RF ion sputtering in dielectrics.•The studied materials are three types of low-permittivity insulators grown on (100)Si.•This reveals as universal damage pattern the generation of two types of point defects.•These include the EX center and a broad signal ascribed to C dangling bonds in carbosilicide clusters. High-resolution electron spin resonance analysis of defects induced by RF ion sputtering has been performed on three different low-permittivity insulators, including chemical vapour deposited carbon-doped SiO2, spin-on glass with subsequent porogen removal by thermal/ultraviolet curing, and layers obtained by self-assembly. The spectra reveal, as the universal damage pattern in all three types of insulators, generation of EX-centers (g=2.0025) and a broad (ΔBpp≈12–15G) signal at g=2.0028 tentatively ascribed to dangling bonds of carbon atoms in a carbosilicide cluster. The differences in defect densities observed between different discharge gasses and different materials are explained by knock off of atoms of different mass from the insulating matrix.