Temperature dependence of the on-state voltage drop in field-stop IGBTs

Abstract

Insulated Gate Bipolar Transistor (IGBT) is the reference design for power semiconductor switches in the range of the medium-high power applications. Different designs were proposed along the development story of this device, but the actual trend is leaded by the Field-Stop IGBT (FS-IGBT) concept. One of the main advantages of this design is the great accuracy in defining the Emitter injection efficiency of the vertical PNP. However a careful design of the Collector side has to be carried out to avoid unwanted effects such as a negative temperature coefficient for the Von of the device. In this work we present the two main cause of the aforementioned effect, with a detailed analysis of the effect of the arising of a Schottky Barrier (SB) at the Collector contact for low doping concentrations.