流体压缩性对微机电系统封装喷射泵点胶特性的影响机理研究

Packaging cost is about 70% of total MEMS (Micro-Electronic-Mechanical-Systems) manufacturing. Fluid dispensing is the key technology of MEMS packaging, and jet dispensers are preferred for high quality and high-speed packaging of small dots. Compressibility is one of fluid properties, which would influence jetting response, dot mass and mass repeatability. This proposal focuses on jet dispensers for MEMS packaging, suggesting to analyze jetting characteristics of jet dispensers with transient compressible flow, impact of fluid compressibility on jetting response, dot mass and mass repeatability, and the coupling of fluid compressibility and piston-nozzle structure. First, the model of the transient compressible flow, and dynamic system model of the jet dispenser will be built. Then dynamic process of jetting would be analyzed, the computational models will be verified with experiments, then to analyze influence of pump structure, working status, compressibility and other properties of the fluid on jetting response, dot mass and repeatability. Furthermore, impact of coupling of fluid compressibility and piston-nozzle structure on jetting response, dot mass and repeatability would be got. Finally, impact of fluid compressibility on pump jetting response could be achieved. So the design approach to jet dispensers and their operation parameter matching technique could be got to perfect the theory of fluid dispensing for MEMS packaging.

封装约占微机电系统制造总成本的70%，点胶是微机电系统封装的关键技术，喷射泵是高质量、高效率微胶量封装的首选。可压缩性是流体的属性之一，会影响喷射泵点胶的动态响应、点胶量和一致性。项目以微机电系统封装喷射泵为对象，提出用可压缩流体非恒定流动理论分析喷射泵的特性，考查流体压缩性对点胶动态响应、点胶量和一致性的影响，及流体压缩性与泵喷嘴—柱塞结构的耦合关系。项目首先建立可压缩流体在泵内流动的瞬态计算模型和喷射泵的系统动力学模型，分析喷射泵的点胶动态过程，并通过试验验证计算模型，从而考查喷射泵结构参数、工况参数、流体压缩性及其它物性参数对点胶动态响应、点胶量和一致性的影响；进一步深入分析流体可压缩性和喷嘴—柱塞结构的耦合对点胶动态响应、点胶量和一致性的影响。从而获得流体可压缩性对喷射泵动态行为的影响规律, 得出喷射点胶泵设计和运行参数匹配的方法, 完善封装胶液分配的理论。

封装是微机电系统制造的重要工艺，点胶是微机电系统封装的关键技术，喷射泵是高质量、高效率微胶量封装的首选。本项目结合流体的属性、机械结构的几何特性以及机械动力学、流体力学研究喷射泵的特性。项目以微机电系统封装喷射泵为主要研究对象。针对毛细管流变仪启动特性进行了详细分析，对推导了其上升时间的线性和半经验公式；建立了喷射泵的过程分析试验平台；建立了喷射泵键合图模型和 AMESim 模型；编写了弱可压缩粘弹性流体两相流数值仿真程序；并设计了驱动压电陶瓷微位移机构的电路。项目建立了可压缩幂律流体在流变仪内流动的瞬态计算模型和喷射泵的系统动力学模型，并通过试验验证了计算模型，分析了毛细管流变仪的动态特性，考查流变仪结构参数、流体粘性参数、流体压缩性对其压力稳定时间（上升时间）影响。编制的数值仿真程序可对粘弹性流体两相流进行仿真分析。可在气动喷射泵键合图模型和 AMESim 模型上进行扩展，进行仿真分析。建立的试验平台可对喷射泵进行喷射过程分析。发表论文 1 篇 (已接收，SCI 刊源)；培养研究生 3 人，已毕业 1 人；参加学术会议 5 次。