Reliability of the Power Module Using the Insulated Substrate with Al/C Composite

Inhalt:
In the direct cooling cold plate with aluminum insulated substrate (DAB: Direct Aluminum Bonding), thermal cycle causes formation of wrinkle at wiring layer (1). In this paper, we report the improvement of reliability in heat cycle and power cycle tests by utilizing the power module bearing insulated substrate with Aluminum/Carbon (Al/C) composite. Aluminum insulated substrate with Al/C composite restricts deformation of Aluminum at heat cycle test. Observed CTE of Al/C composite is virtually identical to the CTE calculated as parallel type in the rule of mixtures, consistent with its layered structure. In such unique structure, CTE of Al/C composite is comparable to that of ceramic, thermal stress can be reduced. By utilizing DAB with Al/C composite for power module, we have successfully fabricated wrinkle-free cold plate after heat cycle.