Diffusion-Free Organic Hole Selective Contacts for Silicon Solar Cells
Li-Yu Li1,2, Chun-Heng Chen1,2, Chi-Lin Chiu1, You-Lan Li1, Hsin-Fei Meng3, Peichen Yu1
1Department of Photonics, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu, Taiwan
/2Green Energy and Environment Research Laboratories, Industrial Technology Research Institute, Hsinchu, Taiwan
/3Institute of Physics, National Chiao Tung University, Hsinchu, Taiwan

The dopant-free carrier selective contacts (CSC) to replace the complex diffusion manufacturing are increasingly explored using a variety of different materials. In this work, we investigate various organic materials, including conductive polymer PEDOT: PSS, fluorescent polymers PFO and Green B,  and small molecules DMFL-NPB, to serve as the hole selective con-tact (HSC). By analyzing the lifetime and implied open-circuit voltage, assessing of contact resistivity and band alignment, as well as the device efficiency, we evaluate the potential of soluble organic materials acting as the HSC. The results have shown that PEDOT: PSS could effectively passivate the silicon surface to increases the open-circuit voltage by 20 mV and the short-circuit current density by 1mA/cm2. Overall, the power conversion efficiency increases from 17.1% to 18.6%.