High rate deposition of highly stable a-Si:H films using multi-hollow discharges for thin films solar cells

We developed a multi-hollow discharge plasma chemical vapor deposition (CVD) method to deposit a-Si:H films of high stability against light exposure for solar cell applications. This method suppresses incorporation of clusters, which are formed in discharges, into films; and such a-Si:H films without cluster incorporation show high stability against light exposure. Aiming at increasing the deposition rate, we have developed a honeycomb type electrode with more than double number of holes, and we have realized deposition of highly stable a-Si:H films of 4.7 × 1015 cm− 3 in stabilized defect density at a rate of 3.0 nm/s and better film thickness uniformity within 5% in an area of 4 cm in diameter.