In order to protect the normal operation of an integrated circuit or a hybrid circuit, it needs to be packaged; and when packaged, a large number of connectors in the circuit are led out of the sealed body. These leads require a certain amount of strength to form the support skeleton of the integrated package circuit, called the lead frame. In actual production, for high-speed mass production, lead frames are usually continuously stamped on a metal strip in a specific arrangement. The frame material accounts for 1/3 to l/4 of the total cost of the integrated circuit, and is used in a large amount; therefore, it must have a low cost.
Copper alloys are inexpensive, have high strength, electrical conductivity and thermal conductivity, and are excellent in processability, needle weldability and corrosion resistance. They can be controlled in a wide range by alloying, and can better meet the performance of lead frames. Requirements have become an important material for lead frames. It is currently the most widely used material for copper in microelectronic devices.