A new type of dual-branch composite structure-based ultrasonic transducer for microelectronic interconnection and packaging

Abstract

A new type of composite structure-based ultrasonic transducer was proposed and a complete set of design methods was systematically developed. The transducer adopts a cascaded structure of two tapered ultrasonic horns and a piezoelectric resonator which involves two groups of piezoceramic stacks. The performance test experiments show that the newly proposed transducer can provide dual-directional vibration output either in a separate excitation of one stack or in a simultaneous excitation of two stacks, depending on which it is expected to execute different bonding tasks in the meanwhile. Particularly in a simultaneous excitation pattern, the salient features in the energy superposition and power-sharing enable the transducer to cope with a higher power-required occasion without rising the input power of any branch transducer, avoiding the potential risk of performance deterioration caused by the excessive self-heating of the piezoceramic stack due to a long-term operation. The test results also show that the newly proposed transducer possesses a good deal of flexibility, manifesting the feasibility and effectiveness of the design idea, as well as the relevant design method, and giving the transducer a wider application prospect.