Preliminary Studies of Copper (I) Iodide as a Potential UV Sensing Material

Copper (I) iodide (CuI) is a p-type semiconductor material with bandgap ~3.1eV. This suggests the possibility of employing CuI as a visible blind-UV photodetector. In this work, a simple CuI UV sensor was fabricated and tested. The sensor platform consisted of tin-plated copper traces in the form of interdigitated arrays on a fiberglass substrate. Meanwhile, CuI powder was prepared using chemical precipitation method. The cleaned and dried powder was dissolved in acetonitrile and drop-dried on the interdigitated arrays. The FESEM images revealed a compact morphology of CuI deposited on the sensor platform. In terms of UV-sensing, CuI exhibited greatest responds under UVA ambient, followed by both UVB and UVC. The sensitivity plot of the CuI UV sensor revealed an average rise and fall time in the tens of seconds. This preliminary study indicated CuI as a potential UV sensing material, which can be improved upon in future.