Patent ID: 8296701

Claim:
A machine-implemented method of designing a semiconductor device, the method comprising: preparing a first design for the semiconductor device; estimating leakage current for the first design; determining, using a processor, a leakage current cumulative distribution function (CDF) for the first design by: calculating a plurality of mean shifts of leakage current and a sum of the plurality of mean shifts, each mean shift of the plurality of mean shifts is calculated around a single global process corner and a single operating voltage; calculating the leakage current at a plurality of global process points and at a plurality of operating voltages to obtain a global leakage current CDF; and shifting each leakage current on the global leakage current CDF by the sum of the plurality of mean shifts to obtain the leakage current CDF for the first design considering both global variations and local variations and for the plurality of operating voltages; preparing a second design for the semiconductor device based on determination of the leakage current CDF for the first design; estimating leakage current for the second design; determining a leakage current CDF for the second design in accordance to the determination of the leakage current CDF for the first design; and selecting one of the first design and the second design based on a comparison of the leakage current CDF for the first design and the leakage CDF for the second design.