Control of radical species in microwave plasma chemical vapor deposition

Abstract

AbstractThe spatial distributions of electron temperature and density in pure Ar plasma in a double‐tubed coaxial‐line type microwave plasma chemical vapor deposition (CVD) system were measured using the probe method. It was found that the electron temperature and electron density dropped sharply in an area 4 cm from the edge of the discharge tube and they decreased slowly in an area farther away from the forementioned area. SiH4 gas was dissociated in Ar plasma, and the electron temperature and density of the plasma were varied by changing the location of the SiH4 gas inlet. As a result, it was found that the fragmentation pattern of radical species could be varied by changing the location of the SiH4 gas inlet.In addition, films were fabricated under various fragmentation patterns and the qualities of these films were evaluated. It was found that the film quality could be improved by dissociating SiH4 gas at low electron temperature.