Accelerated testing of SiO2 reliability

This paper compares several popular accelerated test methods for projecting SiO2 lifetime distribution or failure rate: constant-voltage and constant-current time-to-breakdown and charge-to-breakdown tests, ramp-voltage breakdown test,and ramp-current charge-to-breakdown test. Charge trapping affects the electric field acceleration parameter for time-to-breakdown and the value of breakdown voltage, Practical considerations favor ramp breakdown testing for gate oxide defects characterization, The effective thinning model is used for defect characterization and the ramp-voltage breakdown test is shown to be superior to the ramp-current Q(BD) test for extraction of the defect distribution. Measurement issues are also discussed.