工作条件下超声倒装键合换能系统的阻抗特性

Impedance Property of Flip Chip Ultrasonic Transducer in Working Condition

在建立各子部分等效阻抗的基础上,采用等效电路方法构建工作条件下芯片超声倒装键合换能系统的阻抗/导纳模型。对阻抗模型进行数值计算,并采用频率扫描的方法实测系统的阻抗特性。研究发现,在工作条件下,换能系统100 kHz范围内包含4阶轴向固有频率;相比于空载条件,工作条件下的各阶谐振频率增大,其电阻值增大,电导值降低。实验测试与数值计算结果相互吻合。

Based on the equivalent impedance for the individual part of transducer used in the ultrasonic flip chip bonding,an impedance model of transducer system in the working condition has been established by the equivalent circuit method.The impedance model has been calculated numerically and the impedance property has been verified by the frequency sweeping measurement.It has been found that there were four axial vibration modes of transducer system in 100 kHz.Comparing with the non-working condition,each resonance frequency and its impedance increased while the conductance value decreased when the transducer was in working condition.The results of experiment measurement well agreed well with the impedance model.