One applications of such materials is in active matrix backplanes for displays.
Copper-iodide semiconductor material has a higher electron (hole) mobility than other p-type transparent semiconductors but has faced certain processing issues that have limited its use.
CuI is rarely used as a semiconductor for TFTs because its hole concentration is so high that it can result in uncontrollable conductivity where the usual goal is highly controlled switching from a conductive to a non-conductive state. In addition, conventional solution-based processing of films generally requires a heat treatment, which is energy, time consuming and potentially damaging to pre-existing circuits or features.
The researchers discovered that by making CuI-based thin films even thinner the conductivity could be reduced, controllability enhanced and the films would self-anneal in air at room temperature.
The team tested multiple processing conditions and fabricated various different TFTs to determine the origin of the enhanced device properties and to demonstrate the potential uses of CuI as a thin-film p-type semiconductor and these have been reported in a paper Room-Temperature Solution-Synthesized p-Type Copper(I) Iodide Semiconductors for Transparent Thin-Film Transistors and Complementary Electronics prepared for Advanced Materials.
Related links and articles: