Electrical Properties of a p-SnOx/n-SnOx Diode on a Flexible Polyimide Substrate

In recent years, flexible electronics have been an area of considerable interest due to the development of materials such as transparent semiconductor oxides, which are compatible with flexible substrates. Herein, lithography and magnetron sputtering are used to fabricate a flexible p-n diode of SnOx thin films on a polyimide substrate and electrical characterization is performed by varying the bending cycles. Using specific oxygen concentrations in the reactive gas mixture of the sputtering system, transparent p-SnO0.8 (8.0% ppO(2)) and n-SnO1.2 (18.5% ppO(2)) on polyimide substrates are successfully deposited. Electrical results show the SnOx diode exhibits a threshold voltage of 2.24 V and a great rectification ratio of 10(2). It is found the diode has excellent I-V rectifying behavior even when subjected to bending with a radius of curvature of 10 mm. It is important to note that after 200 bending cycles at a curvature radius of 50 mm, the p-SnOx/n-SnOx diode retains its rectifying behavior, making it attractive for large-scale applications in transparent and flexible electronics.