Patent ID: 6189765
Filing Date: 2001-02-20
Classification: B23K,H01L

Abstract:
A wire bonding apparatus for detecting double wire bonding having a wire spool for providing a wire, a high voltage torch for forming a wire bonding ball on an end of the wire, a capillary for positioning the wire bonding ball and x,y and z-axis drivers for moving the capillary, the wire bonding apparatus comprising:a first means for applying a voltage to the wire and for forming a closed loop through the voltage applied wire and the wire bonding ball;a first comparator for comparing an output from the closed loop with a reference voltage and for outputting a compared result signal;a second comparator, coupled to said first comparator, for receiving the compared result signal and, in response to the compared result signal indicating a low level voltage, said second comparator comparing a present height of the wire bonding ball with a predetermined height; andsaid x,y and z-axis drivers, responsive to said present position being higher than said predetermined height, for moving the capillary to a correct position.