Development of an In-Line Capable Transient Thermal Analysis Equipment for a Power Module with Five Half Bridges

Abstract In this paper, we demonstrate that the structural degradation of a silicon carbide (SiC) power module corresponding to thermal cycles can be detected and tracked non-destructively by transient thermal analysis method. The purpose of this evaluation is to analyze the distribution of the thermal resistance in the power module and to identify the structure deterioration part. The power module with SiC-MOSFET were assembled using ZnAl eutectic solder as device under test. The individual thermal resistance of each part such as the SiC-die, the die-attachment, the AMCs, and the baseplate was successfully evaluated by analyzing the structure function graph. A series of thermal cycle test between −40 and 250°C was conducted, and the power modules were evaluated their thermal resistance taken out from thermal cycle test machine at 100, 200, 500 and 1000 cycles. We confirmed the increase in thermal resistance between AMCs and base plate in each thermal cycle. The portion where the thermal resistance increased is in good agreement with the location of the structural defect observed by scanning acoustic tomography (SAT) observation.

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Evaluation of Thermal Resistance Degradation of SiC Power Module Corresponding to Thermal Cycle Test

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/2380-4491.2017.hiten.223 ◽

2017 ◽

Vol 2017 (HiTEN) ◽

pp. 1-5 ◽

Cited By ~ 3

Author(s):

Fumiki Kato ◽

Hiroki Takahashi ◽

Hidekazu Tanisawa ◽

Kenichi Koui ◽

Shinji Sato ◽

...

Keyword(s):

Thermal Analysis ◽

Thermal Resistance ◽

Thermal Cycle ◽

Test Machine ◽

Thermal Cycles ◽

Power Module ◽

Transient Thermal Analysis ◽

Power Modules ◽

Transient Thermal ◽

High Temperature Operation

Abstract In this paper, we demonstrate that thermal degradation of silicon carbide (SiC) power modules corresponding to thermal cycles can be detected and tracked non-destructively by transient thermal analysis. The purpose of this evaluation is to analyze the distribution of the thermal resistance in the power module and to identify the structure deterioration part. As a target for evaluation power modules using a SiC-MOSFET for high-temperature operation were assembled with Zn-5Al eutectic solder. The junction to case thermal resistance was successfully evaluated as 0.85 K/W by using transient thermal analysis, and the thermal resistance of the Zn-5Al die-attachment was also evaluated as 0.13 K/W. A series of thermal cycle test between −40 and 250°C was conducted, and the power modules were evaluated their thermal resistance taken out from thermal cycle test machine at 100, 200, 500 and 1000 cycles. We identified the increase of thermal resistance each thermal cycle in specific modules. It was successfully shown that thermal resistance deterioration of SiC power module corresponding to thermal cycles can be traced non-destructively by this transient thermal analysis method.

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