IGBT module bonding wire fracture detection method based on ultrasonic reflection

Abstract

The invention discloses an IGBT module bonding wire fracture detection method based on ultrasonic reflection. The IGBT module bonding wire fracture detection method comprises the following steps of S1, building a data acquisition platform, S2, collecting ultrasonic reflection output signals of an IGBT module with the same specification as the target IGBT module under different bonding wire breakage conditions, and performing frequency domain transformation, S3, according to the collected signal data, establishing a database of the relationship between the target IGBT module bonding wire fracture number and the ultrasonic reflection output frequency domain signal, and S4, acquiring an ultrasonic reflection output signal of the target IGBT, comparing the ultrasonic reflection output signal in the established database, and judging the number of broken bonding wires of the IGBT. Ultrasonic reflection is adopted to detect the bonding wire fracture condition of the IGBT module. Compared withother existing detection methods, ultrasonic reflection is used for detecting the bonding wire breakage condition of the IGBT module, and the method has the advantages that the cost is low, the precision is high, and the detection process does not depend on the working point of the IGBT.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for detecting breakage of IGBT module welding wires based on ultrasonic reflection. Background technique [0002] High power converters are key components in power systems, industrial power systems, electric vehicles and many other high power applications. These systems are fundamental and vital components of homes, businesses, and transportation systems, and we want them to have little or no downtime. The IGBT is connected by welding wires inside the module. Electromechanical stress and environmental aging factors (mechanical vibration, heat and radiation) will form cracks on the welding wire itself or the silicon surface to which it is attached. The occurrence of these conditions will reduce the performance of the semiconductor switch and even cause Fault failure. [0003] According to the existing literature, power semiconductor devices are the most prone to failure co...

AI Technical Summary

Problems solved by technology

Scholars have proposed using the spread spectrum time domain detection method to detect degraded IGBTs and other devices, but the spread spectrum time domain detection method has some shortcomings, such as: the center frequency is limited to 48MHz, resulting in limited measurement accuracy; Degradation of the device can be detected with only one measurement; when the number of faulty bond wires is small, the detection results are not very good

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