Thermal contact resistance across a copper-silicon interface

摘要

An experimental setup to measure the thermal contact conductance across a silicon-211u001ecopper (Si-Cu) interface is described, and the results obtained are presented. 211u001eThe resulting thermal contact resistance data are used in estimating the thermo-211u001emechanical and optical performance of optical substrates cooled by interfaced 211u001ecopper cooling blocks. Several factors influence the heat transfer across solid 211u001einterfaces. These include the material properties, interface pressure, flatness 211u001eand roughness of the contacting surfaces, temperature, and interstitial material, 211u001eif any. Results presented show the variation of thermal contact conductance as a 211u001efunction of applied interface pressure for a Cu-Si interface. Various 211u001einterstitial materials investigated include iridium foil, silver foil and a 211u001eliquid eutectic (Ga-In-Sn). As expected, thermal contact resistance decreases as 211u001einterface pressure increases, except in the case of the eutectic, in which it was 211u001enearly constant. The softer the interstitial material, the lower the thermal 211u001econtact resistance, Liquid metal provides the lowest thermal contact resistance 211u001eacross the Cu-Si interface, followed by the iridium foil, and then the silver 211u001efoil.