Ti/Pt/Au back side metallization and eutectic alloys Au6%Si and Au12%Ge have been studied for metallurgical stability and reliability both during soldering process (400 ° C) and prolonged (200 h) high temperature heating (300 ° C). It was found that Pt dissolves in liquid phase Au6%Si (or Au12%Ge) which can put serious adhesion problems in SiC die attachment. An application of vibration during die soldering remarkably shortens soldering time and decreases Pt solubility. The experimentally measured thermal resistance of the so mounted devices on package base plate of golden Cu60%Mo is in the expected range and doesn't change during high temperature test showing high reliability of the devices. It is worth noting, than Ti/Pt/Au metallization and AuSi (or AuGe) eutectic alloy requires high degree of control in soldering process and future high volume production may need better back side barrier layer that Pt one.

Our results from creating and investigation of Ohmic contacts for high power and high temperature SiC devices permit us to conclude that the most suitable system for n-type SiC is contact system Ni/Si/SiC and for p-type SiC we are suggesting the systems Al/Si/SiC and Pd/Si/SiC.

For more higher temperature application the system Ti/Al?SiC can be use.

For packages and packaging for high power and high temperature SiC devices we suggest:

• packages mast be done from the alloy CuMo more frequently Cu60% - Mo40% and Al₂O₃ ceramic;
• for back side metallization we suggest multylayer system Ti/Pt/Au;
• for soldering process we suggest the system Au6%Si/.

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