Unclamped inductive switching stress failure mechanism of LDMOS

The failure mechanism of Unclamped Inductive Switching (UIS) stress on Laterally Diffused MOS (LDMOS) device has been investigated first time. Failure in LDMOS has been compared with the Vertical DMOS. Technology-computer-aided-design (TCAD) simulations and analytical solution reveal that the diffusion current dominates the avalanche current at the drain side to reduce the device stability which depends on the negative value of partial differentiation of diffusion current density with respect to temperature. It is observed that the variation in drain dose affects the diffusion current in turn varying the stability of the device.