Abstract: A heat-dissipating element for the packaging of microelectronic components wherein conduits of higher thermal conductivity material extend through material having a compatible thermal expansion to the microelectronic component material. The element is formed by a porous compact of a high melting temperature material having bores formed between a surface located close to the microchip and a surface for contacting a heat sink or other heat dissipator. The compact is then infiltrated with a lower melting point material having a high thermal conductivity, thereby filling the bores to form heat conduits extending between the surfaces. Further enhancements provide integrated heat reservoir and radiator structures.