Deposition of a-SiNx Films by ArF Laser Induced CVD as Diagnosed by Optical Emission Spectroscopy

Deposition of SiNx films by ArF laser induced chemical vapor deposition has been investigated. The films exhibit excellent electrical properties; the high breakdown voltage and the low fixed charge are the same as in films deposited by LPCVD, but the BHF etching rate of them is larger by a factor about 4 than that prepared by the plasma CVD. The diffusion length of the radicals contributing to the deposition was estimated from the distribution of the deposition rate as a function of the deposition parameters. The optical emission from the radicals produced by ArF laser irradiation was also studied. Using these results, we discuss the mechanism of the deposition.