Patent ID: 7980448

Claim:
A method of forming a bonded body comprised of a first base member, a second base member, and a first bonding film and a second bonding film provided between the first base member and the second base member, wherein the first bonding film and the second bonding film are constituted of copper and an organic component, and an amount of copper contained in each of the first bonding film and the second bonding film is 80 atom % or higher but lower than 90 atom % at an atomic ratio, wherein the method comprising: forming the first bonding film on the first base member by using a chemical vapor-film formation method; forming the second bonding film on the second base member by using a chemical vapor-film formation method; bringing the first bonding film formed on the first base member into contact with the second bonding film formed on the second base member so that the first bonding film faces the second bonding film; and applying a compressive force to the first base member and the second base member so that the first bonding film and the second bonding film are bonded together to thereby obtain the bonded body; wherein in the applying process of the compressive force, when the compressive force to be applied to the first base member and the second base member is 50 MPa, a time of applying the compressive force to the first base member and the second base member is defined as “Y” minutes, a temperature of heating the first bonding film and the second bonding film is defined as “T” K, the amount of copper contained in each of the first bonding film and the second bonding film is defined as “X” atom %, and a gas constant is defined as “R” J/(mol·K), the following relation is satisfied: 1/Y≧1.43×10 9 exp[−6.60×10 −2 (100−X)−82×10 3 /RT].