Time Decay Study of Ag/PEDOT:PSS/μT-Si/In:Ga Heterojunction Solar Cell using Electrochemical Impedance Spectroscopy

Despite years of painstaking effort of solar photovoltaic (SPV) community market share of SPV is still in single digit. One of the principal reason of this is the high thermal budget protocol of Si based PV devices which constituted more than 93% of the market in 2016. High thermal budget protocol of Si PV devices can be replaced by low thermal budget protocol through heterojunction technique. In this technique highly conducting hole transport polymer such as poly(3, 4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is coated over n-Si to fabricate Schottky junction. This study reports fabrication of 9.5% efficiency PEDOT: PSS and Si based heterojunction solar cells. Electrical parameters of the device deteriorates with time. Electrochemical impedance spectroscopy is used to investigate the factors responsible for the deterioration of the electrical parameters of the device.