A preferred embodiment of the invention provides a method for testing a
MISFET to determine the effect of hot carrier injection (HCI) on
integrated circuit lifetime. The method comprises applying a positive
stress voltage to a gate having a high-k dielectric, while simultaneously
holding a drain voltage equal to the stress voltage. Using a stress
voltage that is greater than a normal operating voltage accelerates the
degradation and failure of the integrated circuit. Embodiments include
monitoring electrical parameters such as threshold voltage,
transconductance, linear drain current, or saturation drain current. A
pre-selected shift in a monitored electrical parameter indicates device
failure. Embodiments include analyzing the data by plotting the logarithm
of an accelerated device lifetime versus the gate stress voltage. The
device lifetime under operating conditions is predicted by extrapolating
the plot for a given device operating voltage.