Influence of Passivation Layers on Characteristics of a-InGaZnO Thin-Film Transistors

Abstract

We investigated the influence of passivation-layer deposition on the characteristics of a-InGaZnO thin-film transistors (TFTs). The threshold voltage ( <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">VT</i> ) of the TFTs shifted markedly as a result of the mechanical stress induced by the passivation layers above. By adjusting the deposition parameters during the passivation process, the performance of the TFTs can be modulated. The a-InGaZnO TFTs after dual passivation exhibited good performance with a field-effect mobility of 11.35 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /V·s, a threshold voltage of 2.86 V, and an on-off ratio of 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">8</sup> .