Effect of patterning on the performance of p-type Cu2O TFTs: a 3D simulation using COMSOL multiphysics

A 3D model for p-type Cu2O thin-film transistor (TFT) was simulated for the first time using COMSOL Multiphysics. The main objective of this modeling is to investigate the effect of patterning either the channel or the gate on the performance of Cu2O TFTs. Considering the ideal case, where traps and leakage current are not incorporated, we compared the performance of three different designs; unpatterned, patterned channel and patterned channel and gate TFTs. In each case, the transfer curve, output characteristics, current flow and potential distribution were clarified. The comparison between main parameters showed that the unpatterned model overestimated the field effect mobility µFE by 37.4% over the fully patterned TFT, nevertheless, the latter exhibited the highest on/off current ratio and the lowest off-current. A simulation of experimental output characteristics reported for Cu2O TFT was performed to check the model viability.