A novel piezostack-driven jetting dispenser with corner-filleted flexure hinge and high-frequency performance. (11th April 2018)

• Record Type: Journal Article
• Authors: Bu, Zhenxiang; Lin, Siying; Huang, Xiang; Li, Anlin; Wu, Dezhi; Zhao, Yang; Luo, Zhiwei; Wang, Lingyun
• Is Part Of: Journal of micromechanics and microengineering. Volume 28:Number 7(2018:Jul.)
• Publication Date: 2018-04-11
• Subjects: jetting dispenser -- piezoelectric actuator -- displacement amplifying mechanism -- corner-filleted flexure hinge; Microelectromechanical systems -- Periodicals; Micromechanics -- Periodicals; 621.38105
• DOI: 10.1088/1361-6439/aab80c
• Languages: English
• ISSNs: 0960-1317

Abstract

Abstract: This paper presents a new jetting dispenser which is applicable to high-frequency microelectronic packaging. In order to achieve high frequency glue jetting and improve the stability of jetting dispensers, we redesign a novel displacement amplifying mechanism, and a new on–off valve jetting dispenser driven by piezoelectric actuators is developed. Firstly, the core part of this jetting dispenser—the displacement amplifying mechanism with a corner-filleted flexure hinge—is proposed and a comparison with the previous structure is carried out; then the characteristic dimensional parameters of the amplifying mechanism are determined by theoretical calculation and finite element analysis. Secondly, a prototype of the dispenser with the displacement amplifying mechanism is fabricated based on the determined parameters. We use a laser displacement sensor to test the displacement of the needle, and a maximum amplifying displacement output of 367 µ m is obtained under an applied 200 V to the piezoelectric actuator, which is consistent with the simulation result and meets the requirement of high displacement output. Thirdly, we build an integrated testing system. Mixed glycerol/ethanol is chosen as the experimental dispensing glue, and the experiment and analysis of a droplet diameter are conducted. A higher jetting frequency of 400 Hz and a smaller droplet diameter of 525 µ m are achieved with the glycerol/ethanol mixture, and the characteristics of consistency and temperature influencing the droplet diameter are verified by experiments.