Floating-Body Kink-Effect-Related Parasitic Bipolar Transistor Behavior in Poly-Si TFT

This letter reports the floating-body kink-effect-related parasitic bipolar transistor (PBT) behavior in the poly-Si TFT. As verified by the experimentally measured data and 2-D simulation result using the discrete grain/discrete energy level distributed trap approach, different from traditional bipolar junction transistor where it is dominated by diffusion, the current conduction in the PBT is dominated by drift and leading to a smaller current gain at a large drain voltage due to the dominance of impact-ionization-generated holes.