Controlled thermal expansion, high conductivity and significant strength make AlSiC attractive. Due to cost, this material is typically used in base sections and as substrates for direct die attachment in power module bases. Some applications use this material to form the entire heat sink although due to cost an aluminum extrusion is typically used. Table 1 offers a comparison of various heat sink materials. The problem is that only a few markets currently accept liquid-cooled electronics.
Liquid cooled heat sinks reduce volume over air-cooled parts.
The primary resistance is customer acceptance. The concept of a liquid-cooled personal computer has yet to gain general market acceptance. However, as heat fluxes exceed 100 Watts per square inch, the need for phase change heat transfer or liquid cooling are the only alternatives. Over the last few decades heat dissipation has become an increasing problem for electronics designers. Today the thermal engineer needs to be an integral part of the design team and not an afterthought.