High field induced stress suppression of GIDL effects in TFTs.

摘要

Gate-Induced drain leakage (GIDL) is an unwanted short-channel effect that occurs at higher drain biases in an overdriven off state of a transistor. The GIDL is the result of a deep depletion region that forms in the drain at high drain-to-gate biases. The depletion region causes significant band bending which in-turn allows conductive band-to-band tunneling creating excess current. In a PFET, electrons tunnel from the drain to the body while holes tunnel into the drain.;By utilizing the effects of high energy, or "hot", electrons, the GIDL current in an accumulation-mode PFET can be suppressed. This suppression is thought to be due to local creation of interface charge at the gate-oxide/silicon interface located close to the drain end of the transistor. This charge in-turn creates a mirror charge in the silicon, which acts like a pseudo-asymmetrical lightly-doped drain structure. Up until now, this effect has only been demonstrated on the first order. The goal of this study is to further investigate the effects of high-field stress on the suppression of GIDL in accumulation-mode PFETs. An overview of background information, simulations, fabrication, electrical characterization, and physical characterization are presented in this study.