Palladium plating: A lead free finish for IC leadframes

Concern has grown recently over the amount of lead (Pb) used in electronic products and manufacturing environments. In response, the electronics industry has begun investigating alternatives to traditional tin/lead (Sn/Pb) solders. Several consortia are working to determine the feasibility of Pb-free solder alloys. In 1989 Texas Instruments introduced a revolutionary new leadframe finish to the semiconductor industry. This technology consists of a copper base metal leadframe plated with nickel and palladium. The palladium acts as an oxidation barrier for the nickel which is the soldered surface. This palladium finished leadframe has replaced conventional Sn/Pb coating for greater than 99% of TI's logic and linear devices. No Pb is used in the manufacture of the leadframe or in the assembly of the IC. Devices with TI's palladium lead finish have been identified as a primary test vehicle for Pb-free solders. Components with TI's Pd finish have no Sn/Pb on their surface to influence test results of Pb-free solders. Traditional Sn/Pb plated or dipped components can influence test results when evaluating Pb-free solders. When viable, Pb-free solders are identified and available, the next issue will be to remove Pb from the IC component. TI has more than 8 billion palladium plated devices in the field. TI's Ni/Pd plating technology is a Pb-free alternative for IC manufacturers and users who desire to use Pb-free processes.