On the bias dependence of time exponent in NBTI and CHC effects
On the bias dependence of time exponent in NBTI and CHC effects
复制标题
NBTI 和 CHC 效应中时间指数的偏差依赖性
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
Yu Cao
中科院分区：
文献类型：
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作者：
J. Velamala;V. Reddy;Rui Zheng;S. Krishnan;Yu Cao
NBTI和CHC是两个主要的可靠性问题。它们的退化速率（由时间指数（n）表示）随多个因素而变化，例如测量方法和偏置电压（即，对于亚阈值或线性电流，N不同）。这样的变化显着影响电路寿命的长期预测。通过研究潜在的机制和硅的数据，我们得出结论，偏置依赖性是由于本征器件的非线性。用阈值电压漂移的统一老化模型，一致地解释了不同工作区的不同时间指数。所提出的解决方案捕获在各种电源电压（VDD）下的n的变化，如通过来自晶体管和RO测量的硅数据所验证的。它有助于提高可靠性预测的准确性，减少不必要的设计裕度。基于该结果，由于时间指数的减小，器件和电路的寿命有望在较低的工作电压下得到提高。
NBTI and CHC are two leading reliability concerns. Their degradation rate, which is represented by the time exponent (n), varies with multiple factors, such as the measurement method and bias voltages (i.e., different n for sub-threshold or linear current). Such a variation significantly affects the long-term prediction of circuit lifetime. By investigating the underlying mechanisms and silicon data, we conclude that the bias dependence is due to intrinsic device non-linearity. With a unified aging model of threshold voltage (Vth) shift, different time exponents in different operation regions are consistently explained. The proposed solution captures the change of n under various supply voltages (Vdd), as validated with silicon data from transistors and RO measurement. It helps improve the accuracy in reliability prediction, reducing unnecessary design margins. Based on the result, the device and circuit lifetime is expected to be enhanced operating at lower Vdd due to the reduction in the time exponent.