20% efficiency mg/PCBM/p-type silicon hybrid solar cells

Silicon/organic hybrid solar cells, with relatively simple and low-energy consumption fabrication processes, hold the promise for over-all cost reduction. However, their performances are still not comparable to the commercial crystalline silicon (c-Si) solar cells. Here, hybrid devices with organic phenyl-C61-butyric acid methyl ester (PCBM) layer inserted between metal electrode and textured p-type crystalline silicon (c-Si(p)) substrate are investigated. The quality of the PCBM/c-Si(p) contact is much improved after a SiOx thin layer is formed on the a-Si:H(i) surface and a Voc of 706 mV and an efficiency of 20.0% are achieved on the hybrid solar cells. Analysis of the dark J-V-T characteristics of the hybrid device shows that the junction current is dominated by the minority-carrier diffusion current.