Metal–Insulator–Semiconductor Photodetectors With Different Coverage Ratios of Graphene Oxide

It was found that the introduction of graphene oxide (GO) in metal–insulator–semiconductor (MIS) tunneling diodes can improve the rectifying characteristic and responsivity when acting as a photodetector. In this paper, we tuned the coverage ratio of GO using different degrees of hydrophilic treatments. GO samples with different coverage ratios were compared to identify the role of GO in MIS tunneling diodes. We prove that the improvement is due to the negative fixed charge in the GO layer. It is interesting that the partial coverage of GO results in the best performance.