Influence of ZnO/p+a-Si:H Microcrystallization and Antireflection Coatings on pin a-Si:H Solar Cells Performance

Abstract

AbstractIn general terms this paper analyzes effectiveness of ZnO/p+/i a-Si:H/n+/Al solar cells made on commercial glass substrate with double-sided antireflection coatings. The primary topic, however, is the ZnO/p+/i a-Si:H junction based on layers obtained by the reactive magnetron sputtering (RMS) of Si:B, Si:P, Al, Zn:Al targets, where the “i” layer is a protocrystalline RFCVD layer. These single layers, as well as the respective structures, were studied using primarily Grazing Incidence X Ray Analyzes and AFM spectroscopy. In particular, the microcrystallization, surface roughness and chemical composition of the films were studied with respect to film thickness, RMS power and hydrogen dilution. The nature of the influence of ZnO/p+/i a-Si:H crystallization on pin a-Si:H solar cells performance is presented. Optical transmission and reflection measurements were used to measure the light flux reaching the “i” layer. We determined the experimentally observed angular distribution of scattered light in transmittance through glass/ZnO:Al/p+ silicon and double antireflection coatings on glass/ ZnO:Al/p+ silicon junctions. The optoelectronic properties of glass/ZnO/pin a-Si:H/Cr/Al cells are examined by systematic investigation of their I-V characteristics subsequent to steady-state conditions.