Self-Heating and Kink Effects in SLS Single-Crystal-Like Nanowire Transistors

In this paper, the electrical characteristics of sequential-lateral-solidification (SLS) single-crystal-like nanowire (NW) poly-Si thin-film transistors (TFTs) with various gate structures are compared and comprehensively studied. The self-heating and kink effects of all SLS TFT devices with various gate structures are analyzed. Owing to the nanoscale nitride hard mask, each NW is easily transformed within one crystalline grain of the SLS poly-Si film with the regularly arranged grains; thus, each NW performs with a single-crystal-like device channel. Therefore, NW-type SLS TFTs with gate-all-around (GAA) and trigated (TRI) structures exhibit better electrical characteristics as compared with the conventional planar SLS TFTs. At moderate VGS and VDS biases, GAA devices exhibit better electrical characteristics. However, the self-heating effect and the local electric fields located at three sharp corners result in the severe degradation of electrical characteristics for GAA-SLS TFTs operated or stressed at high VGS and VDS biases.