Failure rate calculation: Extending JESD74/JESD74A to any sample size

The failure rate has been an important index in product reliability. Practitioners in microelectronics reliability have been using JEDEC standards to determine whether a product will pass the requirement of a prespecified failure rate. The limitation of the current
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method used by JESD74 and its revision JESD74A in determining the upper confidence limit for failure rate is pointed out and discussed. Very large relative errors such as 40% have been shown for certain sample sizes which are not sufficiently large enough. This paper provides practitioners an exact method to calculate the confidence bounds of failure rates and therefore makes JESD74 and its revision JESD74A complete to any sample size.