Patent ID: 8535979

Claim:
A manufacturing method of a semiconductor element substrate, the manufacturing method comprising: forming a first photoresist pattern on a first surface of a metallic plate, to form a slit penetrating the first surface of the metallic plate and a second surface different from the first surface, to connect a semiconductor element mounting part, a semiconductor element electrode connection terminal, a wiring, an outer frame part, a four corners of the outer frame part, and a metallic chip being a part of the metallic plate; forming a second photoresist pattern on the second surface of the metallic plate to form an external connection terminal, the outer frame part, and the slit; forming the slit by half etching to connect the metallic chip with the four corners of the outer frame part; forming a plurality of concaved parts on the second surface of the metallic plate; forming a resin layer by injecting a resin to the plurality of concaved parts so that the resin does not enter the slit and hardening the resin; and etching the first surface of the metallic plate and forming the semiconductor element electrode connection terminal and the outer frame, the semiconductor element electrode connection terminal and the outer frame being electrically connected to the semiconductor element mounting part and the external connection terminal.