Impact of transient currents caused by alternating drain stress in oxide semiconductors

Reliability issues associated with driving metal-oxide semiconductor thin film transistors (TFTs), which may arise from various sequential drain/gate pulse voltage stresses and/or certain environmental parameters, have not received much attention due to the competing desire to characterise the shift in the transistor characteristics caused by gate charging. In this paper, we report on the reliability of these devices under AC bias stress conditions because this is one of the major sources of failure. In our analysis, we investigate the effects of the driving frequency, pulse shape, strength of the applied electric field, and channel current, and the results are compared with those from a general reliability test in which the devices were subjected to negative/positive bias, temperature, and illumination stresses, which are known to cause the most stress to oxide semiconductor TFTs. We also report on the key factors that affect the sub-gap defect states, and suggest a possible origin of the current degradation observed with an AC drive. Circuit designers should apply a similar discovery and analysis method to ensure the reliable design of integrated circuits with oxide semiconductor devices, such as the gate driver circuits used in display devices.

[1]  J. Koyama,et al.  Development of Liquid Crystal Display Panel Integrated with Drivers Using Amorphous In–Ga–Zn-Oxide Thin Film Transistors , 2010 .

[2]  Seungwu Han,et al.  Origin of Degradation Phenomenon under Drain Bias Stress for Oxide Thin Film Transistors using IGZO and IGO Channel Layers , 2015, Scientific Reports.

[3]  J. Woicik,et al.  Origin of deep subgap states in amorphous indium gallium zinc oxide: Chemically disordered coordination of oxygen , 2014 .

[4]  E. Fortunato,et al.  Oxide Semiconductor Thin‐Film Transistors: A Review of Recent Advances , 2012 .

[5]  Je‐hun Lee,et al.  Investigation on the negative bias illumination stress-induced instability of amorphous indium-tin-zinc-oxide thin film transistors , 2014 .

[6]  Jerzy Kanicki,et al.  Bias‐stress‐induced stretched‐exponential time dependence of charge injection and trapping in amorphous thin‐film transistors , 1993 .

[7]  T. Fuyuki,et al.  Hot carrier analysis in low-temperature poly-Si TFTs using picosecond emission microscope , 2004, IEEE Transactions on Electron Devices.

[8]  Yang Yang,et al.  Boost Up Mobility of Solution‐Processed Metal Oxide Thin‐Film Transistors via Confining Structure on Electron Pathways , 2014, Advanced materials.

[9]  H. Ohta,et al.  Room-temperature fabrication of transparent flexible thin-film transistors using amorphous oxide semiconductors , 2004, Nature.

[10]  Masashi Kasami,et al.  High-Performance Thin Film Transistor with Amorphous In2O3–SnO2–ZnO Channel Layer , 2012 .

[11]  H. Ohta,et al.  Thin-Film Transistor Fabricated in Single-Crystalline Transparent Oxide Semiconductor , 2003, Science.

[12]  C. Hwang,et al.  Unusual instability mode of transparent all oxide thin film transistor under dynamic bias condition , 2013 .

[13]  T. Kamiya,et al.  Present status of amorphous In–Ga–Zn–O thin-film transistors , 2010, Science and technology of advanced materials.

[14]  Masashi Kasami,et al.  Active-Matrix Flatpanel Displays and Devices — TFT Technologies and FPD Materials — , 2012 .

[15]  Jackson,et al.  Stretched-exponential relaxation arising from dispersive diffusion of hydrogen in amorphous silicon. , 1987, Physical review letters.

[16]  C. W. Lin,et al.  Degradation of the Capacitance-Voltage Behaviors of the Low-Temperature Polysilicon TFTs under DC Stress , 2007 .

[17]  Yukiharu Uraoka,et al.  Thermal analysis of amorphous oxide thin-film transistor degraded by combination of joule heating and hot carrier effect , 2013 .

[18]  Mingxiang Wang,et al.  Dynamic degradation of a-InGaZnO thin-film transistors under pulsed gate voltage stress , 2015 .

[19]  Yu Cao,et al.  Large-scale complementary macroelectronics using hybrid integration of carbon nanotubes and IGZO thin-film transistors , 2014, Nature Communications.

[20]  Hyun Jae Kim,et al.  Electric Field-aided Selective Activation for Indium-Gallium-Zinc-Oxide Thin Film Transistors , 2016, Scientific Reports.

[21]  J. Kanicki,et al.  Density of States of a-InGaZnO From Temperature-Dependent Field-Effect Studies , 2009, IEEE Transactions on Electron Devices.

[22]  Jin Jang,et al.  Time-temperature dependence of positive gate bias stress and recovery in amorphous indium-gallium-zinc-oxide thin-film-transistors , 2011 .

[23]  S. M. Iftiquar,et al.  Bias–stress-induced threshold voltage shift dependence of negative charge trapping in the amorphous indium tin zinc oxide thin-film transistors , 2013 .

[24]  A. Zunger,et al.  Many-body GW calculation of the oxygen vacancy in ZnO , 2009, 0910.2962.