An Improved Hot-Carrier Lifetime Evaluation Method for the n-Type LDMOS With Hot-Hole Injection

The hot-carrier lifetime evaluation method of a 90-V-level n-type lateral double-diffused MOS (LDMOS) is investigated in this brief. Our charge pumping experiments demonstrate that the on-resistance degradation of the device is induced by the combination effect of the hot-hole injection at field oxide region and the interface state generation at field oxide and accumulation regions. Thereby, the hot-carrier lifetime of the device was evaluated by the comprehensive model proposed by Moens, which considers the effects of both hot-hole injection and the interface state generation. However, our experiments found that multiple lifetimes were obtained based on the model proposed by Moens and some lifetimes have the risk of overestimation. To solve the problem, an improved hot-carrier lifetime evaluation method based on a novel semiempirical model is proposed. Further experiments and analyses illustrate that the proposed hot-carrier lifetime evaluation method can provide a definite lifetime that has no risk of overestimation for the investigated LDMOS and has improved the lifetime prediction precision compare to the method based on Hu's model.