Quality and System Reliability
Technical Lecture Session
Reliability of Power Conversion Systems
IGBT, Aging, Ultrasound, Bond wire lift off, Degradation detection
IGBT modules are one of the key elements of power converters. When electrical stress and environmental factors such as temperature, humidity, vibration, and so on are subjected to large IGBT modules, natural degradation takes place, and cracks are formed in bond wire itself and in Si surface where bond wires are attached to the die. These cracks and lift-offs eventually degrade the device performance leading to a complete failure. This paper introduces a novel approach to detect these failures using ultrasound resonators. Experimental results show that the data generated from the ultrasound resonators could be successfully used to detect the bond wire lift off related aging of the IGBT. The outcome of this research strongly implies that it could be the most suitable and direct way to characterize the bond wire lift off related aging level in an IGBT where the results are not operating point dependent.