US Patent 7264146 Ultrasonic tool and ultrasonic bonder

An ultrasonic tool, for bonding two materials to each other by joining a face of one of the materials to a face of the other material using the action of ultrasonic waves applied to one of the materials through another face of the one of the materials, wherein the ultrasonic tool has a coating layer comprising chromium oxide as a main component formed on at least the surface of the tool that is in contact with the face of the one of the materials through which the ultrasonic waves are applied to the one of the materials. An ultrasonic bonder provided with the ultrasonic tool is also disclosed.