Abstract: Ultra-miniature electrical contacts are provided with the strength and resilience necessary to give stable low resistance connection, to minute areas of a device, such as a thousand or so closely spaced surface pads of an integrated circuit. Each contact is initially formed on a substrate as a thin, narrow elongated flat body comprised of selectively deposited layers of metal. Depending on the final configuration desired for the contact, the metal of one metal layer has a coefficient of thermal expansion such as chromium (Cr), and the metal of another layer has a coefficient of thermal expansion such as copper (Cu). Each contact is permanently formed (by differential expansion of the metal layers when heated) into a three-dimensional structure and is then made “robust” by a covering of a specialized stiffening metal plating which adds substantial strength to the contact.

Abstract: Ultra-miniature electrical contacts are provided with the strength and resilience necessary to give stable low resistance connection, to minute areas of a device, such as a thousand or so closely spaced surface pads of an integrated circuit. Each contact is initially formed on a substrate as a thin, narrow elongated flat body comprised of selectively deposited layers of metal. Depending on the final configuration desired for the contact, the metal of one metal layer has a coefficient of thermal expansion such as chromium (Cr), and the metal of another layer has a coefficient of thermal expansion such as copper (Cu). Each contact is permanently formed (by differential expansion of the metal layers when heated) into a three-dimensional structure and is then made “robust” by a covering of a specialized stiffening metal plating which adds substantial strength to the contact.