Skip to Main content Skip to Navigation
Theses

Substrat architecturé et brasure composite sans plomb pour l'électronique de puissance des véhicules électriques ou hybrides : conception et procédés

Abstract : The power electronic modules are essential components for the electric and hybrid vehicles. These electronic modules are generally an assembly of silicon electronic components (transistors and diodes) on copper substrate by soldering. The substrate ensures the mechanical strength and the heat dissipation to obtain a suitable operating temperature (<175°C). The flow of the dissipated power towards the substrate, owing to the fact that this assembly is made of various materials, and because of the thermal gradient, develops shear stresses in the zone of connection (soldered joint) and generates damage in the electronic modules. An ideal substrate would have electric and thermal characteristics close to those of the current substrate (Cu) and a coefficient of thermal expansion close to that of the chips (Si). Such material does not exist. One of the alternative solutions consists in developing a structured material. To reduce the mechanical effects of the differential expansion, an architectured substrate was conceived. The proposed substrate is a composite with its parameters optimized by numerical simulation in order to increase its thermal conductivity and to reduce its macroscopic coefficient of thermal expansion. The properties of the designed composite were validated by experiments. Moreover, we validated the implementation of conventional processes (plating, folding, cutting and bonding) for the new substrate. The fabrication technology proposed rests on roll bonding and several options are compared to produce the optimized architecture. Also, the lead-free alloys used to date in addition to a low solidus temperature, suffer from resistance thermal ageing. Under the effect of heat, the initial solder microstructure can evolve with the development of intermetallics in the form of plates (needles) acting as stress concentration sites and reducing the lifetime of the module. To circumvent this effect, we propose composite solders containing a SnAgCu alloy reinforced by refractory particles with a good thermal conductivity and low CTE.
Document type :
Theses
Complete list of metadatas

Cited literature [162 references]  Display  Hide  Download

https://pastel.archives-ouvertes.fr/pastel-00626665
Contributor : Bibliothèque Mines Paristech <>
Submitted on : Monday, September 26, 2011 - 4:45:08 PM
Last modification on : Thursday, September 24, 2020 - 6:30:04 PM
Long-term archiving on: : Tuesday, December 27, 2011 - 2:35:57 AM

Identifiers

  • HAL Id : pastel-00626665, version 1

Citation

Abderrahmen Kaabi. Substrat architecturé et brasure composite sans plomb pour l'électronique de puissance des véhicules électriques ou hybrides : conception et procédés. Matériaux. École Nationale Supérieure des Mines de Paris, 2011. Français. ⟨NNT : 2011ENMP0024⟩. ⟨pastel-00626665⟩

Share

Metrics

Record views

997

Files downloads

1252