Performance Investigation of an n-Type Tin-Oxide Thin Film Transistor by Channel Plasma Processing

In this paper, we investigated the performance of an n-type tin-oxide (SnO_x) thin film transistor (TFT) by experiments and simulation. The fabricated SnO_x TFT device by oxygen plasma treatment on the channel exhibited n-type conduction with an on/off current ratio of 4.4x10⁴, a high field-effect mobility of 18.5 cm²/V.s and a threshold swing of 405 mV/decade, which could be attributed to the excess reacted oxygen incorporated to the channel to form the oxygen-rich n-type SnO_x. Furthermore, a TCAD simulation based on the n-type SnO_x TFT device was performed by fitting the experimental data to investigate the effect of the channel traps on the device performance, indicating that performance enhancements were further achieved by suppressing the density of channel traps. In addition, the n-type SnO_x TFT device exhibited high stability upon illumination with visible light. The results show that the n-type SnO_x TFT device by channel plasma processing has considerable potential for next-generation high-performance display application.