Enhanced Liquid Metal Micro Droplet Generation by Pneumatic Actuation Based on the StarJet Method

Micromachines

Nils Lass¹  Lutz Riegger¹  Roland Zengerle¹ 

[1] Laboratory for MEMS Applications, IMTEK, Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, 79110 Freiburg. Germany; E-Mails:

关键词: StarJet;    metal droplets;    3D-printing;    rapid prototyping;    droplet generator;    microparticle;    soldering;    bumping;   

DOI  :  10.3390/mi4010049

来源: mdpi

【 摘 要 】

We present a novel pneumatic actuation system for generation of liquid metal droplets according to the so-called StarJet method. In contrast to our previous work, the performance of the device has been significantly improved: the maximum droplet generation frequency in continuous mode has been increased to f_max = 11 kHz (formerly f_max = 4 kHz). In addition, the droplet diameter has been reduced to 60 μm. Therefore, a new fabrication process for the silicon nozzle chips has been developed enabling the production of smaller nozzle chips with higher surface quality. The size of the metal reservoir has been increased to hold up to 22 mL liquid metal and the performance and durability of the actuator has been improved by using stainless steel and a second pneumatic connection to control the sheath flow. Experimental results are presented regarding the characterization of the droplet generation, as well as printed metal structures.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.