COMPOSITE MATERIAL, THERMAL DIFFUSION MEMBER IN CIRCUIT SYSTEM EMPLOYING THE MATERIAL, CIRCUIT SYSTEM AND THEIR MANUFACTURE

摘要

PURPOSE: To make it possible to form a composite metal material with high density and to improve heat dispersion in an iron metal material by combining the iron metal material which has a low coefficient of expansion with a silver metal material, and heating and sufficiently melting the silver metal material and bonding it to the iron metal material. CONSTITUTION: A porous matrix 40a made of iron alloy which has a relatively low coefficient of thermal expansion has many pores 44, which extend penetrating the compound material between both the surfaces 46 and 48 of the compound material. Those pores 44 are filled with the silver metal material which has high thermal conductivity, which are bonded to iron. Then a conduction path of high thermal conductivity is formed between both the surfaces of the compound material. Consequently, the composite material having a relatively low coefficient of thermal expansion is obtained by the new method and a path of silver metal of high thermal conductivity is obtained extending penetrating the combined material. Consequently, heat generated in the device at the time of circuit operation can effectively be dispersed.