Operation time control of a high density packaging using a low melting point alloy

This paper describes a concept of controlling operation time of a high-density packaging using a phase change material (PCM). A low cost alloy, which is composed of Bi/Pb/Sn/In and having melting point less than 343 K, was used as the PCM. Thermal experiments using the alloy were carried out and it was confirmed that the substrate back surface temperature could be kept constant at the melting temperature of the PCM for several minutes by thermal absorption, while the PCM phase changed from its original solid state into the liquid state. Also, in the present work, it was confirmed that thermal network method is practically useful for the thermal design of a package with a PCM.