Semiconductor device manufacturing method and semiconductor device

A semiconductor device manufacturing method comprising the steps of:

• fixing a semiconductor element to a substrate;
• electrically connecting a signal terminal and a main terminal of a terminal aggregate to the semiconductor element, the terminal aggregate comprising a frame portion, the signal terminal connected to an inside of the frame portion, and the main terminal having a larger width than the signal terminal connected to the inside of the frame portion and having an opening formed therein, and forming a to-be-encapsulated body in which the substrate, the semiconductor element, and the terminal aggregate are integrated;
• mounting step for mounting the to-be-encapsulated body on a lower mold half such that a plurality of blocks formed in the lower mold half are meshed with the signal terminal and the main terminal with no space left therebetween, with at least one of the plurality of blocks being placed in the opening formed in the main terminal;
• after the mounting step, placing a bottom surface of an upper mold half on top surfaces of the plurality of blocks, a top surface of the signal terminal, and a top surface of the main terminal with no space left therebetween to form a cavity for placing the substrate and the semiconductor element;
• and
• molding step for performing molding by injecting mold resin into the cavity.