Al-Sic electronic packages with controlled thermal expansion coefficient by a new method of pressureless infiltration

Abstract

A method is described whereby SiC preforms may be infiltrated in air by a molten aluminum alloy to yield a metal matrix composite with thermal expansion coefficients that are suitable for electronic packaging, such as in microwave integrated circuits. Crucible geometries and infiltration conditions may be designed to provide inexpensive and reusable containers and useful section thicknesses in ~1 hr. Intricate geometries may be fabricated in the green state of the ceramic, prior to infiltration, thereby minimizing final machining of the composite.