Patent ID: 7735707

Claim:
A wire bonding apparatus comprising: an ultrasonic horn including a capillary part, an ultrasonic vibrator part, and an ultrasonic horn body portion, the ultrasonic horn body portion being securely-fixed to the capillary part at one end thereof and to the ultrasonic vibrator part at another end thereof; a bonding arm including an ultrasonic horn-connecting portion for fixing securely the ultrasonic horn thereto; a bonding arm body portion provided between the ultrasonic horn-connecting portion and an arm supporting shaft therefor; a pressure sensor for detecting a pressing load applied by the capillary part, the pressure sensor being provided within the bonding arm; the bonding arm being provided with a thin-connecting portion which functions as a supporting point; and the thin-connecting portion being provided at the same height as a height of a center of gravity of the ultrasonic horn and the ultrasonic horn-connecting portion, and at a point where a balance between inertial mass including the ultrasonic horn-connecting portion and the ultrasonic horn except the ultrasonic vibrator part and inertial mass of the ultrasonic vibrator part is maintained when the bonding arm is turned about the arm supporting shaft therefor.