Silicon nitride films prepared by high-density plasma chemical vapor deposition for solar cell applications

Silicon nitride films were deposited by means of high-density inductively coupled plasma chemical vapor deposition in a planar coil reactor. The process gases used were pure nitrogen and a mixture of silane and helium. Buried contact solar cells, passivated by the silicon nitride layer, show efficiency above 17%. Strong H-atom release from the growing SiN film and Si–N bond healing are responsible for the improved electrical and passivation properties of the SiN film. This paper presents the optimal refractive index of SiN for a single layer antireflection (SLAR) coating in solar cell applications.