Dual mode ultrasonic generator in a wire bonding apparatus

Abstract

Abstract The specification sets forth an ultrasonic wire bonding system for bonding wire to an underlying electronic circuit or terminal. The system incorporates a bonding tool connected to a transducer which causes the bonding tool to ultrasonically vibrate and when impressed against a wire lying thereunder, bond said wire to an underlying electronic circuit. The transducer is driven by a generator which generates either a constant current or constant voltage to the transducer while it is bonding. The constant current mode accommodates thick films and stitch bonding which require substantially more force, while the constant voltage mode provides for thin films and ball bonding which requires substantially less ultrasonic force. As a consequence, the generator provides for the foregoing dual mode so as to optimize the bonding characteristics between the two respective bonds that are provided by this invention and is controlled by a host computer, a digital to analog converter (DAC) and a phase detector connected to a reactance modulator with a limiter and a synchronous detector through a power amplifier to a respective transducer that is to be driven in either the constant current or constant voltage mode.

Inventors

• 👤 Hal W. Smith, Jr.

Bibliographic Details