GPD Global: Enhanced Fluid Control for Next-Gen Dispensing
As component sizes shrink, material properties and ways to apply them are posing a challenge to the assembly process. However, technologies that push the limits of current fluid deposition technology are becoming available. Chip Scale Review recently interviewed Christian Vega, Sales Manager for dispense system manufacturer, GPD Global, to learn more about how the company's PCD technology is meeting application demands for tighter fluid control for low viscosity fluids and increased throughput of high viscosity fluids.
CSR: We understand GPD Global focuses on three main applications: fluid dispensing, peel force testing and lead forming. Please tell us about your fluid dispensing technology and applications.
Vega: GPD Global dispense systems are used across a wide variety of applications. Some more common applications are thermal interface management (TIM) in electronic component assembly, underfill for chip scale packages (CSP) and ball grid arrays (BGA) in printed circuit board (PCB) assembly, solder paste for CSP and PCB assembly, conductive epoxies for die attach in electronic component assembly, LED encapsulation with and without phosphor diffuser, and many more. There are two primary dispense technologies. First is the refined auger technology that enables Microdot dispense pump to reach deposits down to 0.006" (0.150mm) diameter and accurately control small volumes. Recently introduced is the newest, and most exciting dispense technology, Progressive Cavity Displacement (PCD) technology, which enables customers to control low viscosity fluids with much greater accuracy to improve throughput and repeatability with higher viscosity materials.
CSR: Can you give us some more details on how this technology works?
Vega: PCD is a continuously volumetric dispense pump (Figure 1). The dispense method is based on a single helix rotor that rotates within a double helix stator. As the rotor rotates, fluid is trapped in the cavities between the helixes and is moved through the pump. Each of the chambers is sealed from the next so it is not possible for low viscosity fluids to drip. (Picture your finger over the end of a straw). Since the system is not based on chambers that need to be recharged when empty, the system is continuously volumetric, which means it doesn't need to stop in the middle of a process or component to recharge. There are also no timing components that can be influenced by wear or assembly. The main advantage to the end user is a continuously volumetric dispense for a wide range of viscosities. The customer won't need to tweak air pressure or dispense speed when the viscosity of a fluid changes due to pot life or temperature. Low viscosity fluids don't drip onto the product, and additionally an increase in throughput for high viscosity fluids can be realized.
Figure 1: PCD continuously volumetric dispense pump.
CSR: What would you say are the key benefits of PCD?
Vega: The three main advantages to this technology include greater control of low viscosity fluids; tighter tolerances on repeatability, such as with LED packages, or wet-out areas with underfill ;increased throughput with high viscosity fluids such as thermal grease and the ability to dispense volumetrically throughout the pot life of the fluid.
CSR: So how do the results of this technology compare with traditional auger and jetting dispense methods?
Vega: In side-by-side tests, PCD has proven to significantly improve throughput and lower cycle times compared to auger and jetting dispense methods. Micro dispensing down to 1nl is possible while retaining the ability to dispense beads or area fills (Figure 2).
Figure 2: Current testing yields line widths of 0.025 mm (0.010").
CSR: Let's switch gears and talk a bit about the business side of GPD. How important is a global customer base to GPD Global? What advantages does this bring customers?
Vega: Although we are a US based company, 75% of our business is exported outside the United States, with Asia being the primary recipient. We support multinational companies throughout the world with our factory trained technicians and supply like equipment and identical processes. Over the years we have developed dispensing knowledge and experience that we use to help our customers rapidly implement dispense solutions for new product applications. We also continually work with material suppliers, testing fluids and improving the dispense process, throughput and quality.
CSR: In today's economy, successful companies have had to change their traditional ways of doing business. What are some examples of how GPD Global has had to think smarter to stay ahead of competition?
Vega: GPD Global has placed a greater emphasis on assisting customers with process development. In almost every instance, new and existing customers work closely with our global process development team to overcome difficult process challenges. Additionally, we introduced the PCD dispense technology to resolve problems customers had with traditional dispensing valves such as dripping, volumetric inconsistencies, long set-up times and pump maintenance.
CSR: Will GPD be launching any new products in the next few months?
Vega: PCD technology was a major introduction in 2010, we will continue to develop the market place for this series of products, including additional enhancements going forward.
CSR: What would you say was the highlight of GPD Global's year in 2010 and what are you most looking forward to in 2011?
Vega: Our highlight of 2010 had to be the interest in our PCD continuously volumetric dispense technology and the immediate success realized so early on by some of our customers that implemented it in their production process. In 2011, we look forward to continued growth, acceptance and expansion of the application base of this revolutionary dispense technology.