NBTI效应对时钟树门控时钟偏移的影响  

NBTI Effect on the Clock Skew of Clock Tree Circuits

作　　者：陈寿面[1] 李小进[2] CHEN Shoumian;LI Xiaojin(Shanghai Integrated Circuit Research ＆ DevelopmentCenter Ltd, Shanghai 201200, China;East China Normal University, Shanghai 200241, China)

机构地区：[1]上海集成电路研发中心有限公司,上海201200 [2]华东师范大学,上海200241

出　　处：《集成电路应用》2017年第12期24-28,共5页Application of IC

基　　金：国家自然科学基金(61574056)

摘　　要：负偏压不稳定性(NBTI)会造成PMOS器件退化,导致电路性能下降。时钟树网络是同步时序电路的关键,随着电路工作时间推移,NBTI会造成时钟树时钟偏移改变,降低时序电路的整体性能,严重造成电路失效。依据40 nm CMOS工艺NBTI反应/扩散(RD)静动态模型对反相器的传递延迟进行建模,将反相器延迟表征成负载电容、输入转换时间和阈值电压变化的函数,并应用于带门控时钟网络分析,发现通过网络负载调整可以有效缓解NBTI效应对时钟树时钟偏移的影响。Negative bias temperature instability（NBTI） increasesthe threshold voltage of PMOS devices, leading to the device degradation and lowering circuit performance. The clock network is the key component of sequential circuit.As the time elapsing, the clock skew of the network is changed by the NBTI degradation. It deteriorates the timing of the digital circuit. In this paper, based on the static/dynamic NBTI reaction/diffusion models ofthe 40 nm CMOS process, the propagation delay of inverter has been built up. The propagation delay wasperformed as a function of the capacitive load, the input transition time and the threshold change, caused by the NBTI effect. It is found that the impact of NBTI on non-gated clock tree can be alleviated by balancing the capacitive load of its nodes.

关 键 词：NBTI 时钟偏移 门控时钟 反应/扩散(RD) 建模 

分 类 号：TN432[电子电信—微电子学与固体电子学]