3D Metal Microstructure Fabrication using a Molten Metal DoD Inkjet System

In this paper, we present high aspect ratio 3D metal micro column and 65deg-inclined micro column made by molten metal DoD inkjet system. A design, fabrication and performance test of the DoD metal-jet system are introduced for application to the molten metal such as lead free solder. In the experimental test, we set up the test apparatus for visualization of the droplet ejection and measure the ejected droplet volume and velocity. As a result, the diameter, volume and the velocity of the ejected droplet are about 65 -70 mum, 145 -180 pi and 4 m/sec. Finally, we can fabricate vertical and inclined 3D micro column structures using the molten metal inkjet system. The measured geometries of the micro column structures are about height of more than 2,100 mum, diameter of 200 mum and aspect ratio of 10.5 for vertical micro column and l,400 mum of height and 150 mum of diameter for 65deg-inclined micro column, respectively.