Solution-Processed Cupric Oxide P-type Channel Thin-Film Transistors

Thin films of cupric oxide (CuO) with various solution concentrations are deposited on the glass substrates via solution processing, as suggested for p-type semiconductors with non-toxic requirement. The effect of the solution concentration ranging from 0.15 M to 0.30 M was examined. We observed that the CuO thin films were single phase, polycrystalline with monoclinic crystal structure and were oriented along planes, such as (110), (-111), (111) and (-202). The micrographs of the scanning electron microscopy were observed to verify that the grain size of the CuO thin films increased with increases in the solution concentration. In addition, the CuO thin films showed a minimum resistivity of 0.0359 Ωcm, corresponding to the solution concentration of 0.30 M. Finally, the thin film transistors using the solution-processed CuO channel exhibited a p-type operation, with an on/off current ratio of approximately 102-103, and saturated field-effect mobility of approximately 10−4 cm2V−1s−1. © 2020 Elsevier B.V.