An Applied Model for HCI and Lifetime Prediction of LDMOSFET

Abstract

Hot carrier injection (HCI) degradation has been an important problem limiting the life of semiconductor devices. In this work, the degradation of threshold voltage (V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</inf> ) induced by HCI is evaluated for power laterally diffused metal oxide semiconductor field effect transistor (LDMOSFET). The experiment results demonstrate that V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</inf> degradation presents a significant dependence of stress bias, size and temperature. Then an applied model is proposed to characterize the degradation induced by HCI, and are validated with a series of sized LDMOSFET under different stress bias and temperature. An excellent agreement is obtained between the measured and modeled V <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">TH</inf> degradation. Based on the proposed degradation model, HCI lifetime of LDMOSFET is also predicted. The proposed model here are reliable to evaluate the fabrication process, optimize the device structure of power LDMOSFET.