Defect Detection Rate through IDDQ for Production Testing

With the miniaturization of the diffusion process, the leak current per transistor tends to increase and the number of transistors per die tends to become larger, thus rendering more difficult the discrimination through the absolute value of IDDQ (quiescent power supply current) that is required to detect defects on VLSI (Very Large Scale Integration). While various statistical methods have been disclosed, this paper describes first the effects of an increase in the average value of IDDQ due to process dispersion on the IDDQ distribution and presents a theorization to estimate the defect detection rate of various IDDQ testing methods. Corroborative results will then show the validity of the presented theory on the defect detection rate of IDDQ.