考虑偏置温度不稳定性的软差错率分析

Bias Temperature Instability-aware Soft Error Rate Analysis

纳米工艺下,老化效应与软差错共同引发的集成电路可靠性问题至关重要。该文分析偏置温度不稳定性(BTI),包括负偏置温度不稳定性(NBTI)和正偏置温度不稳定性(PBTI)对软差错率的影响,提出从关键电荷值和延迟两个因素综合考虑。首先分析BTI效应下两个因素如何变化,推导了延迟受BTI影响的变化模型,介绍关键电荷的变化机理。然后探讨将两个因素结合到软差错率(SER)评估中,推导了融入关键电荷值的SER计算模型,提出将延迟的变化导入到电气屏蔽中的方法。基于ISCAS89基准电路上的实验验证了综合两种因素考虑BTI效应评估SER的有效性和准确性。

Under nano-scaled technology, the Integrated Circuit （IC） reliability issues caused by both aging mechanism and soft error become very critical. In this paper, from critical charge and delay points of view, the effects of Bias Temperature Instability （BTI）, including Negative BTI （NBTI） and Positive BTI （PBTI）, on Soft Error Rate （SER） are analyzed. Firstly, how BTI affects critical charge and delay is focused on. The delay increasing model is derived, and the critical charge changing procedure is introduced. Further, using the derived SER computational model considering critical charge, and mapping the changed delay into electrical mask procedure, the SER is accurately calculated. Experimental results on ISCAS89 benchmark circuits show that, considering two factors of BTI, SER estimation has high accuracy.