Physics and characterization of various hot-carrier degradation modes in LDMOS by using a three-region charge-pumping technique

Abstract

Degradation of lateral diffused MOS transistors in various hot-carrier stress modes is investigated. A novel three-region charge-pumping technique is proposed to characterize interface trap (Nit) and bulk oxide charge Q(ox) creation in the channel and in the drift regions separately. The growth rates of N-it and Q(ox) are extracted from the proposed method. A two-dimensional numerical device simulation is performed to gain insight into device degradation characteristics in different stress conditions. This paper shows that a maximum I-g stress causes the largest drain current and subthreshold slope degradation because of both N-it generation in the channel and Q(ox) creation in the bird's beak region. The impact of oxide trap property and location on device electrical characteristics is analyzed from measurement and simulation.