Patent ID: 6672503
Filing Date: 2004-01-06
Classification: B23K,H01L

Abstract:
A method of bonding wires between a semiconductor die and a substrate on which the die is mounted the method comprising the steps of:providing an ultrasonic transducer comprising an ultrasonic wave generation device, an ultrasonic vibration amplifying device coupled at one end to the ultrasonic wave generation device, a bonding tool coupled to the opposite end of the ultrasonic vibration amplifying device, and a mounting structure locate between the ends of the ultrasonic vibration amplifying device; performing a first wire bond by operating the ultrasonic transducer at a first ultrasonic frequency; and performing a second wire bondby operating the ultrasonic transducer at a second ultrasonic frequency, the second ultrasonic frequency being different from the first ultrasonic frequency; and selecting the first and second ultrasonic frequencies from among the frequencies of vibration of the energy generation device at which the vibration amplitude is: (i) substantially zero at an energy generation plane which is: perpendicular to a longitudinal axis extending between the ultrasonic generation device, the bonding tool, and the energy generation plane: and intersects the ultras generation device: (ii) substantially zero at a mounting plane which is: perpendicular to the longitudinal axis and coincident with a mounting contact point between the mounting structure and a wire bonding machine on which the transducer is mounted; and (iii) non-zero at a bonding plane which is: perpendicular to the longitudinal axis; and intersects the bonding tool.