Semiconductor module and insert molding method

An insert molding method, comprising:

• forming a pre-molded resin member by injecting a first resin material into a first metal mold, the pre-molded resin member including a terminal fitting portion having a first groove and a pin insertion portion having a hole;
• mounting a combination of the first terminal, the second terminal, and the pre-molded resin member in a second metal mold by fitting the first terminal into the first groove of the terminal fitting portion and inserting a pin, arranged in a cavity of a second metal mold, into the hole of the pin insertion portion;
• mounting a third terminal, different from the first terminal and the second terminal in the second metal mold;
• and
• injecting a second resin material into the cavity of the second metal mold in which the combination of the first terminal, the second terminal, the pre-molding resin member and the third terminal are mounted to mold an external connection terminal by injection molding.