Package deflection and mechanical stress of microelectronic packaging is minimized in a two step manufacturing process. In a first step, a ceramic insulator is high-temperature bonded between a wraparound lead layer and a buffer layer of a same material as the lead layer to provide a symmetrically balanced three-layer structure. In a second step, the three-layer structure is high temperature bonded, using a lower melt point braze, to a heat spreader. This package configuration minimizes package deflection, and thereby improves thermal dissipation and reliability of the package.