An Investigation On Leakage Current Characters And Mechanisms Of Metal-induced Laterally Crystallized N-type Polysilicon Thin Film Transistors Under Hot Carrier Stress

The leakage current characters and mechanisms of metal-induced laterally crystallized n-type polysilicon thin film transistors are investigated under the hot carrier(HC) stress. And current models of metal-induced laterally crystallized n-type polysilicon thin film transistors are identified before and after the hot carrier stress. Finally, a unified quantitative model of n-type TFTs'leakage currents under the HC stress, which can be divided into the field enhanced generation(FEG) and the thermal generation(TG) mechanisms, is presented.The whole research focuses on two aspects, the FEG leakage currents and the TG leakage currents. Take measures in the forward mode and the reserve mode, respectively. Not only analyse the characters of the FEG and TG leakage currents, but also quantitatively analyse the two significant parameters, Ioff and Ioff_min which is defined as the minimum leakage current. Moreover, the study about the TG leakage current can be divided into two contrasting teams, non-hydrogenated TFTs and hydrogenated TFTs. And study the characters of the leakage current in the increasing region and the saturation region under the HC stress, respectively. Finally, the characters of FEG and TG leakage currents in the forward and reverse modes under the HC stress are obtained. And the underlying mechanisms are clarified. Furthermore, the FEG and TG current models of metal-induced laterally crystallized n-type polysilicon thin film transistors are identified before and after the hot carrier stress in the forward and reverse mode, respectively. A unified quantitative model of n-type TFTs'leakage currents under the HC stress is presented. The limiting factors aboutΔIoff andΔIoff_min are clarified in mathematics.