Surface metallization of contact pads

摘要

A long-term stable contact system for interconnection technologies is provided by surface metallization of conducting areas of an electronic device. A protective barrier such as a photoresist is applied to the device and patterned to expose the conductive areas to be coated, e.g. silver contact pads. The conductive areas are cleaned with alkaline and acid solutions and a layer of nickel is deposited from solution. A layer of gold is solution-deposited on the nickel layer and the protective barrier is removed. The clean surface of the conducting area may be activated with a palladium solution and chemically reduced with a copper solution prior to nickel deposition.