Performance and reliability testing of modern IGBT devices under typical operating conditions of aeronautic applications J.L. Fock-Sui-Too a,b,c, * , B. Chauchat b , P. Austin a,b , P. Tounsi a,b , M. Mermet-Guyennet b , R. Meuret c a LAAS-CNRS Laboratory, 7 Avenue du Colonel Roche, 31077 Toulouse, France b ALSTOM Transportation – Power Electronics Associated Research Laboratory, Avenue du Docteur Guinier, 65600 Séméac, France c Hispano-Suiza Company, Rond Point René Ravaud, 77551 Moissy-Cramayel, France article info Article history: Received 2 July 2008 Available online 13 August 2008 abstract As for railway traction applications, aeronautical power electronics implies high power density handling. Moreover typical aeronautical applications impose a harsh thermal environment. SiC technology has recently emerged for high power and high temperature application, but is not yet mature enough. Con- sequently it is still important to push the silicon devices temperature limits in order to increase the amount of switched power. Device ageing is accelerated and there exists the risk of catastrophic failure by thermal runaway. In order to design correctly high temperature power systems, knowing the IGBT characteristics at extended temperature ranges becomes essential. This paper describes an experimental setup and test procedure conceived to experiment with different available IGBT technologies at temper- atures beyond the limits rated by manufacturers (À55 °C, +175 °C). The aim is to characterize the devices for a better understanding and optimized safe application. This will ease prototyping for future develop- ment of IGBT modules in aircraft. Ó 2008 Elsevier Ltd. All rights reserved. 1. Introduction The aeronautics industry is more and more interested in power electronics due to the more electrical aircraft (MEA) vision. As elec- trical energy becomes more and more present in aircraft, the study of power electronics system under harsh thermal environment re- lated to aeronautics applications is essential. Nowadays, power insulated gate bipolar transistor (IGBT) has been largely used for medium power applications range thanks to its good trade-off between switching speed, on-state voltage drop and ruggedness. Researches in the field of power semiconduc- tor technology are continuously improving. Increasing the switch- ing frequencies, on-state characteristics [1] and searching to decrease switching energy losses without degrading on-state per- formance [2] are the main topics. Increasing the switched power implies an increase of the silicon junction temperature which leads to an accelerated ageing of the components. The degradation of the device performances can give rise to thermal instabilities during switching operation that can lead the IGBT to catastrophic failure. In literature many experimental studies explore the possibility of increasing the junction temperature limit, beyond the limits established by manufacturers, in order to increase power capabil- ities. Comparative studies between NPT and PT IGBT technologies [3–5] show that NPT IGBT temperature limit is found to be around 230 °C while thermal runaway can be observed for PT IGBT even below 150 °C when operated at high frequency. Trench IGBT has been also explored at high and low temperature [6,7]. In this context, the knowledge of IGBT performances and de- tailed electrical characteristics at extended temperature becomes essential to system designers. It is necessary to dispose of an experimental facility, adapted for the thermal characterization of power devices at high and low temperature. The aim of the test bench is to obtain accurate current and voltage waveforms from power die components. It is important to be able to extract the intrinsic electrical characteristic of the component instead of using power modules bought commercially. Built around the die and adaptable to any IGBT component, the experimental facility is rel- ative low cost and allows a large temperature exploration without changing the system. The thermal characterization shows the effi- ciency of such test bench. Exploration of the power system behaviour at large range tem- perature will serve to obtain in one hand, a large database of the components performances, and in the other hand the possibility of optimizing the cooling system or the increase of the switched power for the same package characteristics, depending on the re- sults. The most rugged devices are going to be used in the power module prototypes for aeronautics applications. 0026-2714/$ - see front matter Ó 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.microrel.2008.07.051 * Corresponding author. Address: LAAS-CNRS Laboratory, 7 Avenue du Colonel Roche, 31077 Toulouse, France. Tel.: +33 (0) 5 6253 4349; fax: +33 (0) 5 6253 4481. E-mail address: jlfocksu@laas.fr (J.L. Fock-Sui-Too). Microelectronics Reliability 48 (2008) 1453–1458 Contents lists available at ScienceDirect Microelectronics Reliability journal homepage: www.elsevier.com/locate/microrel