Patent ID: 8499825

Claim:
A method for manufacturing a power module, the method at least comprising a step of forming metal powder into a coating film on a surface of a base material by spraying the metal powder comprising copper or copper alloy in a solid state onto the base material surface together with compressed gas, the method being characterized in that: the metal powder is an electrolytic powder, in the film forming step, a spraying pressure at which the metal powder is sprayed onto the base material surface is set so that the coating film has a porous structure, the metal powder is heated so as to be sprayed onto the surface of the base material at a temperature condition of between 50° C. and 200° C. to form the coating film, and after the film forming step, at least the coating film is thermally treated in an inert gas atmosphere under a temperature condition of between 200° C. and 700° C., such that the oxide present at the boundary between fractions of the metal powder diffuses among the grains.