Instability of p-channel poly-Si thin-film transistors under dynamic negative bias temperature stress

Degradation of p-channel poly-Si thin-film transistors (TFTs) under dynamic negative bias temperature (NBT) stress has been investigated. Two-stage degradation behavior is first observed. In the first stage, significant positive threshold voltage (Vth) shift occurs. The dynamic effect which is associated with pulse falling time (tf) and amplitude may be responsible for the instability. Short tf and high amplitude will introduce more significant dynamic effect. After a long time stress, “turnaround” behavior in the Vth is observed. Equivalent DC negative bias temperature instability is the dominate degradation mechanism.

[1]  J. R. Ayres,et al.  Negative gate bias instability in polycrystalline silicon TFT's , 1995 .

[2]  Noriyoshi Yamauchi,et al.  Polycrystalline silicon thin films processed with silicon ion implantation and subsequent solid-phase crystallization: Theory, experiments, and thin-film transistor applications , 1994 .

[3]  Comprehensive Study on Reliability of Low-Temperature Poly-Si Thin-Film Transistors under Dynamic Complimentary Metal-Oxide Semiconductor Operations , 2002 .

[4]  B. Zhang,et al.  Polysilicon Thin Film-Transistors With Uniform and Reliable Performance Using Solution-Based Metal-Induced Crystallization , 2007, IEEE Transactions on Electron Devices.

[6]  Dynamic Negative Bias Temperature Instability (NBTI) of Low-Temperature Polycrystalline Silicon (LTPS) Thin-Film Transistors , 2008, IEEE Electron Device Letters.

[7]  Jam-Wem Lee,et al.  Negative Bias Temperature Instability in Low-Temperature Polycrystalline Silicon Thin-Film Transistors , 2006, IEEE Transactions on Electron Devices.

[8]  Ieee Singapore Section. Reliability,et al.  Proceedings of the 1995 5th International Symposium on the Physical & Failure Analysis of Integrated Circuits , 1995 .

[9]  Mingxiang Wang,et al.  Negative Bias Temperature Instability Dominated Degradation of Metal-Induced Laterally Crystallized p-Type Polycrystalline Silicon Thin-Film Transistors , 2009, IEEE Transactions on Electron Devices.

[10]  B. Zhang,et al.  Degradation of solution based metal induced laterally crystallized p-type poly-Si TFTS under DC bias stresses , 2008, 2008 IEEE International Reliability Physics Symposium.