Characteristics of Aluminum-Doped Zinc Oxide Films Grown Using Facing Target Sputtering for Transparent Electrode of Heterojunction Solar Cells

Abstract

In general sputtering, material characteristics can be degraded by high-energy particles located inside the plasma owing to the thin film surface. However, facing target sputtering (FTS) can be used to produce high-quality thin films through maximum control over substrate damage and the reduction of layer damage caused by high-energy particles impacting the substrate. Transparent conductive oxides (TCOs) are being applied to a variety of technologies, including displays and solar cells. The typical transparent electrode material is indium tin oxide (ITO), which contains rare and expensive raw materials. Aluminum-doped zinc oxide (AZO) has attracted increasing attention as a substitute to ITO because it is composed of abundantly available resources and is generally inexpensive. In this study, an AZO thin film was prepared using an FTS system for heterojunction solar cells. The effects of the deposition substrate temperature on the resulting electrical conductivity, structural properties, and optical properties of the AZO thin films were examined.