| 摘要 |
PURPOSE:To obtain a lead frame which can be mounted in a high density by forming with conductive foils when forming circuit element placing parts, mutual wirings and external lead wirings on both front and back surfaces of a flexible insulating plate, opening through holes capable of flowing sealing resin at the plate, and mutually connecting the foils through the holes. CONSTITUTION:A desired mask pattern is formed by a photoetching method in a dual in-line type lead frame by employing as a flexible insulating plate 10 to make a substrate a polyimide film, bonding conductive foils on front and back surfaces. In other words, semiconductor chip plating parts 1, 2, 3, internal mutual wirings 4, 5, external lead wirings 6, 7 and frame 16 are formed on the front and back surfaces of the plate 10. Then, through holes 8, 9 capable of flowing sealing resin are opened at the prescribed positions of the foils of the plate 10, and necessary mutual wirings are formed of fine metal wires. In this manner, an integrated circuit may be contained in a sole sealed enclosure, thereby improving the integration. |
