Research On High-frequency Ultrasonic Transducer System For Wire Bonding

In this dissertation,aiming at improving the performance and quality of the wire bonder and the conversion efficiency of the ultrasonic energy,a methodology for designing high-frequency ultrasonic transducers is proposed,and the influences of material on the performance of the ultrasonic transducers are studied in detail,and the match-drive circuit is also designed.The following works and achievements have been accomplished.1. Based on vibration and wave theory,utilizing the similarity between mechanical vibration and electrical resonance,the model of ultrasonic concentrator and transducer are both formulated,and the electromechanical equivalent circuitry of transducer system has been established. The initial parameters of the transducers made of duralumin,stainless steel and titanium alloy,have been determined, respectively.2. The optimal models are obtained through ANSYS based on their initial models.By elaborately investigating the vibration characteristics of the optimal models,the conclusion is obtained,that the performance of the duralumin transducer is the best in the three models,and the titanium alloy model is much better than the stainless steel one.3. Based on the Phase-Locked Loop(PLL) CD4046,the match circuit has been designed, which includes frequency track,filter,amplifier and electric circuit match.At the same time,a detailed study has been done on the match of ultrasonic transducer,and it was founded that the electric circuit match can be ignored for low-power ultrasonic transducers.4. The ultrasonic transducers are tested using the impedance analyzer and laser Doppler vibrometer,and the results shows remarkable assembly with anlysis results.The work accomplished in this dissertation lays a foundation for the further research of wire bonding,and supplies some methods and practical experience for the research of the ultrasonic transducer system.