Analytical yield prediction considering leakage/performance correlation

Abstract

In addition to traditional constraints on frequency, leakage current has emerged as a stringent constraint in modern processor designs. Since leakage current exhibits a strong inverse correlation with circuit delay, effective parametric yield prediction must consider the dependence of leakage current on frequency. In this paper, a new chip-level statistical method to estimate the total leakage current in the presence of within-die and die-to-die variability is presented. A closed-form equation for total chip leakage that models the dependence of the leakage current distribution on different process parameters is developed. The proposed analytical expression is obtained directly from pertinent design information and includes both subthreshold and gate leakage currents. Using this model, an integrated approach to accurately estimate the yield loss when both frequency and power limits are imposed on a design is then presented. The proposed method demonstrates the importance of considering both these limiting factors while calculating the yield of a lot