Semiconductor device including semiconductor element and lead-free solder bonding material and method for manufacturing the same

A method for manufacturing a semiconductor device that has a semiconductor element including a main surface on which a connection electrode is provided and a back surface located on a side opposite to the main surface, the method comprising:

• (a) a step of supplying a first bonding material onto a first member and further disposing the semiconductor element on the first bonding material such that the first member and the back surface of the semiconductor element face each other with the first bonding material interposed therebetween;
• (b) a step of melting the first bonding material at a temperature higher than 260° C. to bond the back surface of the semiconductor element and the first member to each other by the first bonding material after the step (a);
• (c) a step of supplying a second bonding material onto the main surface of the semiconductor element after the step (b);
• and
• (d) a step of disposing a second member on the second bonding material, and heating the second bonding material at a predetermined temperature to bond the main surface of the semiconductor element and the second member to each other by the second bonding material after the step (c),
• wherein
• the first bonding material is lead-free solder having a melting point higher than 260° C. and a thermal expansion coefficient smaller than that of Zn—Al-based solder, and
• the second bonding material contains a high-melting-point metal having a melting point higher than 260° C., and a compound of Sn and the high-melting-point metal, and a proportion of the high-melting-point metal by weight contained in the second bonding material is 10 to 40%.