Authors:
Jean-Michel Missiaen (Univ. Grenoble Alpes, France),
Nicolas Botter (Safran SA, France),
Yvan Avenas (Univ. Grenoble Alpes, France),
Rabih Khazaka (Safran SA, France)
Abstract:
An assembly for power electronics based on the deposition and pressureless sintering of successive silver layers on an Aluminum Nitride heat sink has been developed. Sintered silver layers act as die attach, current tracks and adhesion layer on the ceramic. This assembly has the advantage to give sintered joints with a high mechanical strength and a high thermal conductivity compared to standard brazing alloys at the highest operating temperature of semiconductor components (200°C). In this paper, aging of the silver tracks and die attach layers is studied. A significant coarsening of the microstructure is observed in confined areas, under the chip and|or far from the external surface, after 200h annealing in air at 200°C, whereas coarsening is essentially inhibited in argon atmosphere. The shear strength and thermal properties of the sintered joint are improved after thermal storage in air. Mechanisms of the microstructural evolution and microstructure-properties relationships are discussed.
DOI:
https://doi.org/10.59499/WP225372071