Measurement of Infant Mortality Rate in InGaP/GaAs Heterojunction Bipolar Transistor Technology

A novel circuit for measuring the infant mortality rate in InGaP/GaAs HBT technology is presented. The circuit allows reliability stressing to be performed on as many as 100,000 transistors per wafer and is necessary in order to predict the infant circuit failure rate in circuits with >500 transistors. This new circuit allows for the identification of failed transistors and subsequent failure analysis to allow for process improvements. Results show that substrate dislocations are the leading cause of infant mortality