| 摘要 |
PURPOSE:To readily form a lead frame with many fingers with bumps by forming bumps at the ends of the fingers by pressing the frame formed on a substrate together with the substrate by electroforming, and then separating the lead frame from the substrate to obtain the lead frame. CONSTITUTION:A resist layer 9 of the desired pattern is formed on a substrate 8 made of a conductive metal, and the shape of a nonresist portion 8a is formed in a lead frame shape of the desired pattern. A metal layer is formed only on the nonresist portion 8a except the layer 9 by electroforming. Thus, part of a laminate of the substrate 8 and the metal layer 10 formed in one plate shape is pressed, bent, and the layer 10 is separated from the substrate 8 to obtain fingers 4. The ends of many fingers 4 extended inward from the frame portion 5a of the lead frame 7 are bend downward, and are formed in circular bumps 4b through a neck 4a. The ends are formed in circular shape to allow the bonding position of a semiconductor chip 1 with recessed electrode to displace laterally of the fingers 4. |
