Silicon nitride ARC thin films by new plasma enhanced chemical vapor deposition source technology

Hydrogenated silicon nitride (SiN:H) is prized for its ability to anti-reflect incident sun light on crystalline silicon and provide defect passivating hydrogen. An innovative new plasma source, the Plasma Beam Source™ (PBS™) [1] is used to deposit these SiN:H thin films to meet - and exceed - the throughput and quality requirements of this application. This new PECVD technology is capable of depositing SiN:H thin films at rates in excess of 150 nm-m/min with an optical index that is controlled between 1.75 and 2.4. The advantages of this new PECVD technology for solar cell fabrication include exceptional deposition rates, high precursor utilization, dense high quality films with extended production campaigns. In this paper we discuss the results of our process development for hydrogenated silicon nitride thin films. We present bond densities, refractive index, extinction coefficients and hydrogen concentration of deposited films.