Control of trap density in channel layer for the higher stability of oxide thin film transistors under gate bias stress

Abstract

In this study, we investigated turn‐on voltage (VON) stability of oxide‐based TFTs under constant voltage stress for the TFTs including intrinsic ZnO, Hf‐doped ZnO, and Hf‐Zn‐Sn‐O channel layer. Also, to verify the effects of interfacial trap density on the TFTs stability, we employed SiNX and SiO2/SiNX as gate insulator, respectively. We found that the low trap density of the TFTs, including the interfacial trap density between channel and gate insulator, and oxide semiconductor bulk trap density is intimately related to excellent gate bias and temperature stability.