METHOD FOR MANUFACTURING POWER MODULE SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To reliably form a desired fine circuit pattern in a power module substrate where a plurality of metal layers are laminated on an insulating layer.SOLUTION: A method for manufacturing a power module substrate is provided, which includes: an aluminum plate joining step of stacking and joining an aluminum plate for forming a circuit layer on a surface of a ceramic substrate for forming an insulating layer; a first resist forming step of forming a first resist layer on the aluminum plate; an aluminum layer etching step of etching the aluminum plate to form an aluminum circuit layer; a copper plate joining step of stacking a copper plate so as to cover at least the whole upper surface of the aluminum circuit layer, and heating the copper plate at a temperature lower than an eutectic temperature of copper and aluminum to join the copper plate to the aluminum circuit layer by solid-phase diffusion; a second resist forming step of forming a second resist layer on the copper plate; and a copper layer etching step of etching the copper plate to form a copper circuit layer in a desired pattern.