Method for producing ceramic-aluminum bonded body, method for producing power module substrate, ceramic-aluminum bonded body, and power module substrate

Abstract

A method for producing a ceramic-aluminum bonded body obtained by bonding a ceramic member and an aluminum member, the aluminum member before bonding being composed of aluminum having a purity of 99.0 mass % or higher and 99.9 mass % or lower, includes a heat treatment step of subjecting the aluminum member to a heat treatment in a range of 400° C. or higher and lower than a solidus temperature, and a bonding step of bonding the aluminum member after the heat treatment step and the ceramic member via a brazing filler material including Si.

1  and  2 . (canceled) 
     
     
         3 . A ceramic-aluminum bonded body obtained by bonding a ceramic member and an aluminum member,
 wherein the aluminum member before bonding is composed of aluminum having a purity of 99.0 mass % or higher and 99.9 mass % or lower, and   a grain boundary length L, which is observed in a section of the aluminum member after bonding in a thickness direction, per mm 2  is 0.1 mm or less.   
     
     
         4 . A power module substrate, comprising:
 a ceramic substrate; and   an aluminum plate that is bonded to the ceramic substrate,   wherein the aluminum plate before bonding is composed of aluminum having a purity of 99.0 mass % or higher and 99.9 mass % or lower, and   a grain boundary length L, which is observed in a section of the aluminum plate after bonding in a thickness direction, per mm 2  is 0.1 mm or less.   
     
     
         5 . The power module substrate according to  claim 4 ,
 wherein the thickness of the aluminum plate is in a range of 0.05 mm or more and less than 0.4 mm.