针对微型器件封装对非接触式微胶量的需求, 研制了压电驱动微点胶器, 利用压电陶瓷管挤压毛细管产生的瞬时变形实现了微胶滴的分配。分析了毛细管内的流体行为及液滴形成条件; 基于多物理场耦合的方法, 建立了压电微喷的三设备(压电陶瓷、毛细管、胶体)耦合模型。然后, 讨论了驱动电压、喷嘴直径、胶体黏度对控制胶滴形成的影响。在构建的实验平台上, 开展了控制胶滴形成的实验研究。分析了多控制参数(喷嘴直径、胶体黏度、电压幅值、脉冲宽度)的复合作用, 通过匹配相应的参数实现了pL级微胶滴的非接触式分配。实验结果显示: 使用黏度为30 mPa·s胶体, 直径为10 μm的喷嘴, 在驱动电压幅值为50 V, 脉冲宽度为37 μs等参数配置下, 可获得最小胶滴的体积为8.31 pL。实验结果验证了所提出方法和研制工具的有效性。

For the requirement of micro components in bonding for non-contact micro-dispensing volumes, a piezoelectric micro-dispenser was designed and fabricated. The dispensing of micro-droplets was implemented by the instantaneous deformation from the extrusion between the capillary tube and the piezoelectric ceramic tube. The fluid behavior and droplet forming conditions in the capillary were analyzed, and a coupling model including a piezoelectric ceramic, a capillary and a fluid was established by using multidiscipline coupled-field analysis method. The influences of the driving voltage, nozzle diameter and the fluid viscosity on droplet formation were analyzed. An experiment to control the droplet formation was performed in an experimental platform. The compound actions of multiple parameters (nozzle diameter, fluid viscosity, voltage magnitude and pulse width) were discussed based on experiments. The non-contact micro-dispensing of the micro droplets with a size of pL level was achieved by matching the corresponding parameters. Experimental results indicate that the minimum droplet volume of 8.31 pL is obtained when the parameters are set by the fluid viscosity of 30 mPa·s, the nozzle diameter of 10 μm, the voltage magnitude of 50V and the pulse width of 37 μs. These results verify the feasibility of the proposed method and the fabricated micro-dispenser.