Localized Photoluminescence Imaging of Bi‐Layered Cuprous/Cupric Oxide Semiconductor Films by Synchrotron Radiation

Abstract

To develop multi‐layered semiconductor film devices, like a solar cell device, effects of localized impurities and layered interface mismatches on photovoltaic properties should be understood quantitatively and controlled effectively. However, the research of localized photoluminescence on layered semiconductor film devices is delayed. This is because, unfortunately, a measurement method for photoluminescence properties with spatial resolution on the sub‐micron scale, which could provide much of the local photoluminescence properties in bulk multi‐layered film semiconductor devices, has not been developed. In this study, a mapping method for local photoluminescence properties has been developed by utilizing a focused synchrotron radiation beam to evaluate localized photoluminescence affected by microstructures in bi‐layered semiconductor films. Luminescence maps of copper oxide semiconductor film which varies in emission energy and position are successfully obtained under the conditions of a focused beam size of 5 μm in width and 300 nm in height. The possibility of investigation for localized photoluminescence related with the microstructure is strongly suggested. This technique will support and enhance the development of high‐performance multi‐layered semiconductor film devices.