A method for forming a high thermal conductivity heat sink to IC package interface is disclosed. The method uses reactive getter materials added to a two phase solder system having a phase change temperature that is about the normal operating temperature range of the IC, to bind absorbed and dissolved oxygen in the two phase solder interface material at or near the air to solder surface. Over time this chemical binding action results in an oxide layer at the air to solder surface that slows the rate of oxygen absorption into the solder interface material, and thus reduces the harmful oxidation of the solder to IC package interface and the solder to heat sink interface.