Study on the process of fluid Jet dispensing based on high and low voltage drive

Abstract

The Jet dispensing technology plays a decisive role in microelectronic packaging, which is an important link to ensure the quality of microelectronics packaging. With the reduction of the size of components, the high efficiency and low cost in the field of microelectronics packaging, the technical requirements for Jet dispensing are also getting higher and higher. The piezoelectric jetting dispensing as a non-contact dispensing mode, which is not high requirement about the work of the substrate flatness and height. And it has the advantages of high precision, high efficiency and good consistency, so it has an irreplaceable position in the field of microelectronic packaging. This paper is based on the high and low voltage driving method of piezoelectric spray Jet dispensing valve. At the theoretical level, FLUENT software is used to establish two-dimensional axisymmetric model of fluid dispensing, and simulate the formation process of droplets. Because the different high and low pressure will cause the needle's different velocity, the effect of different velocity on the spray effect and the volume of the droplet is simulated. In the experiment, UV glue (industry commonly use, 0.9Pa · s) is used, and a perfect piezoelectric jet dispensing experiment platform is set up, including laser displacement sensor, piezoelectric jet dispensing valve, three axis motion platform and driving power. laser displacement sensor is used to measure the needle's displacement and velocity and cylinder is used to measure droplet volume of different high and low voltage drive. High and low voltage is used to control the displacement, furthermore, which can be used to study the effect on spray droplet size and volume of spray droplets. Under the condition that droplets can be sprayed out, the minimum volume of droplets is 35.3nL.