Chapter 4 - Solution-Processed Crystalline Silicon Heterojunction Solar Cells

Abstract

This chapter describes the state of the art of solution-processed, n-type crystalline Si (n-Si) heterojunction with organic thin-layer (HOT) solar cells using conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS). A single junction of PEDOT:PSS/n-Si solar cells on a plane n-Si substrate showed a power conversion efficiency (PCE) of 13.3%. Then, the PCE increased to 15.4% by adding an antireflection layer. In addition, the solar cell module using 10 units of series-connected 2×2cm2 (4-in.)-sized PEDOT:PSS/n-Si solar cells exhibited an 0.37W (7.2W). Furthermore, PCE increased to 15.8%–18.2% for the front-PEDOT:PSS/n-Si device on textured n-Si substrate using charged mist deposition (CMD) method. In this discussion, we demonstrate the effect of the optical anisotropy of PEDOT:PSS on the photovoltaic (PV) performance of PEDOT:PSS/n-Si heterojunction solar cells, along with the junction property at the PEDOT:PSS/n-Si interface.