Next-Generation Transparent Conducting Oxides for Photovoltaic Cells: An Overview

Transparent conducting oxides (TCOs) are becoming a more critical element in thin-film photovoltaic devices. In the continued drive to increase efficiency and stability while reducing cost and optimizing performance, the optical, electrical, and materials properties of TCOs gain increasing importance. TCOs can perform a variety of important functions, including contacts, antireflection coatings, and chemical barriers. In this paper, we will review some of the current advances in the field of transparent conductors and, where possible, will relate these advances to thin-film photovoltaic devices. Highlights will be on the rapidly growing collection of new n- and p-type materials; the implications of these materials on PV have not been fully assessed.