Method of fabricating an electronic power module by additive manufacturing, and associated substrate and module

A method of fabricating an electronic power module by additive manufacturing, the electronic module comprising a substrate having an electrically insulating plate presenting opposite first and second faces, with a first metal layer arranged directly on the first face of the insulating plate, and a second metal layer arranged directly on the second face of the insulating plate;

• at least one of the metal layers being made by a step of depositing a thin layer of copper and a step of annealing the metal layer;
• and
• the method further comprising a step of forming at least one thermomechanical transition layer on at least one of the first and second metal layers, said at least one thermomechanical transition layer comprising a material presenting a coefficient of thermal expansion that is less than that of the metal of the metal layer, wherein said at least one thermomechanical transition layer is deposited by depositing a powder bed of material or by spraying powder material, the deposited powder being set by scanning with a heat power source in an inert atmosphere.

A method of fabricating an electronic power module by additive manufacturing, the electronic module comprising a substrate having an electrically insulating plate presenting opposite first and second faces, with a first metal layer arranged directly on the first face of the insulating plate, and a second metal layer arranged directly on the second face of the insulating plate;

• at least one of the metal layers being made by a step of depositing a thin layer of copper and a step of annealing the metal layer;
• and
• the method further comprising a step of forming at least one thermomechanical transition layer on at least one of the first and second metal layers, said at least one thermomechanical transition layer comprising a material presenting a coefficient of thermal expansion that is less than that of the metal of the metal layer, wherein the substrate comprises, on at least one of the first and second faces of the insulating plate, a stack of a metal layer and a plurality of thermomechanical transition layers, with said at least one stack presenting a gradient in its coefficient of thermal expansion, and wherein the gradient in coefficient of thermal expansion decreases with increasing distance of a layer of said at least one stack from said substrate.