Amorphous-crystalline silicon heterojunction solar cells formed by the DC saddle field PECVD system: A deposition parameter optimization

The DC Saddle Field PECVD system was used to deposit hydrogenated amorphous silicon (a-Si:H) layers for high efficiency amorphous-crystalline silicon heterojunction (ACSHJ) solar cells. The plasma controlling parameters; including the chamber pressure, gas phase dopant concentration for the p-type a-Si:H (a-Si:H(p+)) emitter, and substrate temperature were varied. The substrate temperature was found to be a critical parameter for the deposition of intrinsic a-Si:H as epitaxial formation can occur with just a temperature increase of 10°C. The processing capabilities have been developed to construct ACSHJ solar cells with 15.5% conversion efficiency for a 4.2 cm2 area.