| 摘要 |
PURPOSE:To improve the strength and heat resistance of the lead frame of a semiconducor element by providing the lead frame composition used for the semiconductor element containing Cu alloy consisting of 0.5-3.5wt% of Fe, 0.3-20wt% of Zn and the residue of Cu and normal impurities. CONSTITUTION:An alloy containing Cu alloy consisting of 0.5-3.5wt% of Fe, 0.3-30wt% of Zn and the residue of Cu and normal impurities is molded in a low frequency melting furnace. The billet thus obtained is hot extruded and cut at its surface. The billet is then cold rolled, intermediately annealed, and cold rolled repeatedly, and finally cold rolled at 55% to thereby form a plate having a thickness of 0.5mm. The plate is then heat treated at 650 deg.C for 30min. Since this plate contains Zn which incorporates dissolving property and strong deoxidizing capacity, it does not produce an oxide detrimental for plating process. Since the plate also contains Fe higher than solid solution limit to thereby deposit iron particles, its strength and heat resistance are increased. |
