Reliability of Contacts for Press-Pack High-Power Devices

Reliability of high-power silicon diodes with different anode contact material (Al, PtSiCu, PtSiCuAu) was tested in the conditions of free-floating silicon in pressed package. Pressure, thermal and cycling tests were applied without foils to buffer excessive loading. Thin PtSi layer was found too brittle for usage in so hard conditions. Copper stacks with thin PtSi interlayer provide low voltage drop and show potential to survive such hard stress conditions under thermal and power load cycle. 5 μm thick PtSiCu contacts showed the best thermo-mechanical properties.