Patent ID: 6132529
Filing Date: 2000-10-17
Classification: C22C,C22F,H01L

Abstract:
In a leadframe comprising a single frame structure for supporting leads on IC chips, the improvement wherein the leadframe is made of a high-strength, high-electroconductivity copper alloy, the copper alloy being made by a process which comprises preparing an ingot of a copper alloy consisting essentially of 0.05-0.40 wt. % Fe, 005-040 wt. % Ni, 0.01-0.30 wt. % P and the balance being Cu and incidental impurities, heating the ingot to a temperature of 800 to 950.degree. C. and hot working the ingot to a reduction ratio of 50% or more, quenching the resultant hot worked material at a temperature from 600.degree. C. or above down to a temperature of 300.degree. C. or below at a cooling rate of at least 1.degree. C./second, heat treating the resultant quenched material at a temperature of 380 to 520.degree. C. for 60-600 minutes without performing cold working, and subsequently performing cold working and a heat treatment at a temperature of 450.degree. C. or below, said high-strength, high-electroconductivity copper alloy having contained therein an Fe--Ni--P system intermetallic compound which is precipitated in a Cu matrix as uniform and fine grains not larger than 50 nanometers, said high-strength, high-electroconductivity copper alloy having a Vicker's hardness (Hv) of 163 or more, a tensile strength of 534 N/mm.sup.2 or more, an electrical conductivity of 69.8% IACS or more and a superior amenability to bending work.