Modeling of IGBT Short-Circuit Behavior

Abstract

Power electronic applications require components with highly efficient switching capabilities. The switching imposes electrical and thermal stresses on the components especially when defects occur. So it is necessary to know the extreme working limits for different loads. The aim of this paper is to analyse the short‐circuit behavior of the electrothermal insulated gate bipolar transistor (IGBT). The electrothermal modeling is based on the physical approach of the semi‐conductor fundamental equations and the thermal equation. The transport phenomena are described using the classical drift–diffusion model. Advanced mobility models taking into account the high electric field and the semi‐conductor surface effects have been used in the transport equations. The simulations have been carried out on a basic cell of the IGBT, using Davinci software. Simulations and experiments show that two destructive phenomena are possible: an immediate failure and a delayed break. The delayed break has been analysed using current, electric field, carrier concentration and temperature curves. In this case, the break is initiated by a thermal mechanism. The characteristics of this mechanism have been analysed and discussed. Electrical and thermal influences have been studied separately. The origin of the destructive phenomena is interpreted by a self‐supply mechanism of the parasitic transistor.

A physically based thermal model for high‐voltage thin‐film SOI LDMOS in short circuit operation

“…In the same figure, the good agreement between theory and simulation results is observed with the exception of the 150 d V = V case, where the simulation temperature profile is lower than theory as a consequence of the thermal-coupling effect. This discrepancies would be overcame by implementing the model in an embedded thermal network which interchanges information with an electrical network by successive loop simulation [7].…”

“…The required conditions to consider Eq. (7) as an accurate thermal approach are the following. (a) An isothermal substrate at ambient temperature is fixed as initial condition at zero time.…”

“…On the contrary, when the threshold voltage, mobility and carrier saturation velocity are significantly modified by the S-H effect, the electro-thermal coupling must be considered. In such a case, the proposed theoretical model for heat generation can be used to design a multiple-node heat source thermal sub-circuit within the device electrical network model [7].…”