To make the sectional form of a film rectangular and the thickness uniform with precise positioning by forming a metal board to which a thermoplastic adhesive is applied into the form of a lead frame by punch pressing or etching.
A screen plate where the thickness of an emulsion resistant to a mesh number 200 and N-methyl-2-pyrrolidone is set to be 100μm, and an opening part larger than the part of the die pad of the lead frame by about 15% is designed on the metal board 1. Then, the frame is positioned along reference holes and an adhesive is printed. A printed thermoplastic polyimide resin is used for adhesive 2. Then, it is punched-pressed and is cut into the forming shape of a lead frame having the die pad. Thus, the section form becomes almost rectangular and the ideal coated film form is obtained.
HOSHINO TATSUMI
MAKINO SHIGEO
ICHIKAWA KIICHI
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