Method for manufacturing metal laminated substrate for semiconductor element formation and metal laminated substrate for semiconductor element formation

Abstract

Disclosed is a metal laminated substrate for forming an epitaxial growth film for forming a semiconductor element having high biaxial crystal orientation on a surface of a metal substrate and a method of manufacturing the metal laminated substrate. The manufacturing method includes the steps of activating at least one surface of a metal plate T 1 by sputter etching or the like; activating at least one surface of a metal foil T 2 made of Cu or a Cu alloy which is cold-rolled at a rolling reduction of 90% or more; laminating the metal plate and the metal foil such that an activated surface of the metal plate and an activated surface of the metal foil face each other in an opposed manner and applying cold rolling to the metal plate and the metal foil which are laminated to each other at a rolling reduction of 10% or less, for example; and biaxially orienting crystals of the metal foil by heat treatment at a temperature of not lower than 150° C. and not higher than 1000° C.

1 . A method of manufacturing a metal laminated substrate for forming a semiconductor element comprising the steps of:
 activating at least one surface of a metal plate;   activating at least one surface of a metal foil made of Cu or a Cu alloy which is cold-rolled at a rolling reduction of 90% or more;   laminating the metal plate and the metal foil such that an activated surface of the metal plate and an activated surface of the metal foil face each other in an opposed manner and applying cold rolling to the metal plate and the metal foil which are laminated to each other; and   biaxially orienting crystals of the metal foil by heat treatment.   
     
     
         2 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein the activation treatment is performed by sputter etching. 
     
     
         3 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein the cold rolling is performed at a rolling reduction of not more than 10% at the time of lamination. 
     
     
         4 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein the metal foil made of Cu or the Cu alloy has a thickness of not less than 7 μm and not more than 50 μm. 
     
     
         5 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein the foil made of the Cu alloy contains not less than 0.01% and not more than 1% of Ag, Sn, Zn, Zr, O and N in total. 
     
     
         6 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein the heat treatment after the lamination is performed at a temperature of not lower than 150° C. and not higher than 1000° C. 
     
     
         7 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein before the heat treatment, a polish treatment is applied to the metal plate such that the surface roughness of a metal-foil-side surface of the metal plate becomes not less than 1 nm and not more than 40 nm by Ra. 
     
     
         8 . The method of manufacturing a metal laminated substrate for forming a semiconductor element according to  claim 1 , wherein a protective film having a thickness of not less than 1 nm and not more than 10 μm is further formed on the metal laminated substrate which is manufactured by the method of manufacturing a metal laminated substrate. 
     
     
         9 . A metal laminated substrate for forming a semiconductor element which is manufactured by any one of the manufacturing methods according to  claim 1 .