Transient liquid phase (TLP) bonding is a promising advanced die-attach technique for wide-bandgap power semiconductor and high-temperature packaging. TLP bonding advances modern soldering techniques by raising the melting point to over 500 °C without detrimental high-lead materials. The bond also has greater reliability and rigidity due in part to a bonding temperature of 200 °C that drastically lowers the peak bond stresses. Furthermore, the thermal conductivity is fractionally increased 67 % while the bond thickness is substantially reduced, lowering the thermal resistance by an order of magnitude or more. It is observed that Au-In TLP bonds exude excellent electrical reliability against thermal cycling degradation if designed properly as experimentally confirmed in this work.