Negative bias temperature instability in low-temperature polycrystalline silicon thin-film transistors
Negative bias temperature instability in low-temperature polycrystalline silicon thin-film transistors
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DOI：
10.1109/ted.2006.885543
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发表时间：
2006-12-01
影响因子：
3.1
通讯作者：
Lei, Tan-Fu
中科院分区：
文献类型：
--
作者：
Chen, Chih-Yang;Lee, Jain-Wem;Lei, Tan-Fu
作者证明负偏压温度不稳定性（NBTI）是低温多晶硅薄膜晶体管（LTPS TFT）的一个重要可靠性问题。测量结果表明，阈值电压漂移与晶界陷阱态的产生高度相关。这两个物理量都遵循几乎相同的幂律依赖于应力时间；也就是说，对应力电压和环境温度的倒数具有相同的指数依赖性。此外，阈值电压漂移与亚阈值摆动退化密切相关，亚阈值摆动退化源于悬空键的形成。通过扩展为体硅 MOSFET 提出的模型，引入了一个新模型来解释 UPS TFT 的 NBTI 退化机制。
The authors have proved that negative bias temperature instability (NBTI) is an important reliability issue in low-temperature polycrystalline silicon thin-film transistors (LTPS TFTs). The measurements revealed that the threshold-voltage shift is highly correlated to the generation of grain-boundary trap states. Both these two physical quantities follow almost the same power law dependence on the stress time; that is, the same exponential dependence on the stress voltage and the reciprocal of the ambient temperature. In addition, the threshold-voltage shift is closely associated with the subthreshold-swing degradation, which originates from dangling bond formation. By expanding the model proposed for bulk-Si MOSFETs, a new model to explain the NBTI-degradation mechanism for UPS TFTs is introduced.