State detection of bond wires in IGBT modules using eddy current pulsed thermography

Li, Kongjing, Tian, Gui Yun, Cheng, Liang, Yin, Aijun, Cao, Wenping and Crichton, Stuart (2014). State detection of bond wires in IGBT modules using eddy current pulsed thermography. IEEE Transactions on Power Electronics, 29 (9), pp. 5000-5009.


Insulated gate bipolar transistor (IGBT) modules are important safety critical components in electrical power systems. Bond wire lift-off, a plastic deformation between wire bond and adjacent layers of a device caused by repeated power/thermal cycles, is the most common failure mechanism in IGBT modules. For the early detection and characterization of such failures, it is important to constantly detect or monitor the health state of IGBT modules, and the state of bond wires in particular. This paper introduces eddy current pulsed thermography (ECPT), a nondestructive evaluation technique, for the state detection and characterization of bond wire lift-off in IGBT modules. After the introduction of the experimental ECPT system, numerical simulation work is reported. The presented simulations are based on the 3-D electromagnetic-thermal coupling finite-element method and analyze transient temperature distribution within the bond wires. This paper illustrates the thermal patterns of bond wires using inductive heating with different wire statuses (lifted-off or well bonded) under two excitation conditions: nonuniform and uniform magnetic field excitations. Experimental results show that uniform excitation of healthy bonding wires, using a Helmholtz coil, provides the same eddy currents on each, while different eddy currents are seen on faulty wires. Both experimental and numerical results show that ECPT can be used for the detection and characterization of bond wires in power semiconductors through the analysis of the transient heating patterns of the wires. The main impact of this paper is that it is the first time electromagnetic induction thermography, so-called ECPT, has been employed on power/electronic devices. Because of its capability of contactless inspection of multiple wires in a single pass, and as such it opens a wide field of investigation in power/electronic devices for failure detection, performance characterization, and health monitoring.

Publication DOI:
Divisions: Engineering & Applied Sciences
Additional Information: © 2013 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Full Text Link: http://ieeexplo ... rnumber=6654355
Related URLs:
Published Date: 2014-09
Authors: Li, Kongjing
Tian, Gui Yun
Cheng, Liang
Yin, Aijun
Cao, Wenping ( 0000-0002-8133-3020)
Crichton, Stuart



Version: Accepted Version

Export / Share Citation


Additional statistics for this record