Highly Enhanced Performance of Network Channel Polysilicon Thin-Film Transistors

This letter presents the electrical characteristics of newly proposed network-channel low-temperature polysilicon channel (LTPS) thin-film transistors (TFTs). Due to effective reduction of grain boundary traps and enhanced gate controllability, the network-channel TFTs show better subthreshold slope, lower threshold voltage, and higher ON- OFF current ratio, compared with conventional planar devices. The extracted grain boundary trap density and the interface trap density are significantly reduced in the network-channel devices. In addition, the network-channel devices show higher immunity to hot-carrier stressing, which are confirmed from the low-frequency noise characteristics with various stressing time. These results suggest that the network-channel devices are very promising for next-generation LTPS TFT applications.