JEM’s Mission: Improve Electronics Manufacturing through the use of Advanced Equipment

1When JAVAD EMS (JEMS) opened in 2010, it was based on two things: One was the volatility that its owners experienced as an OEM within the Tier 3 EMS space in Silicon Valley and the other was the belief that both equipment and process investments must be made in order to keep up with the company’s own technology needs and end product quality requirements. Starting this venture in an economic downturn provided the opportunity to buy used equipment at bargain prices; however, the company made the conscious decision to buy new equipment that could meet the most complex products and technologies of the future. Advanced equipment and processes allow JEMS to build advanced/complex products and do so with the highest levels of quality, whether it is a prototype build or a production-level build. All are built the exact same way on the exact same equipment. “While we cannot eliminate entirely the need for human intervention in the manufacturing process, we do all we can to provide advanced automation, maximum knowledge and repeatable/defined processes to our operators,” commented Gary Walker, Vice President at JEMS. JEMS purchased and installed an Aegis MES system that provides detailed work instructions at point-of-use via touch screens from the screen printing process all the way to the pack-out process for a finished product. This guarantees that all operators are using the latest revision document for them and that the process parameters they will use or inspect to have been clearly defined and validated for their use. This ensures continuity and consistency from job to job. It is a workflow-based system so a defined process is established for each product and by placing bar code serial numbers on every board that is processed, the company not only tracks finite quality details to an individual board level but also controls the flow of each and every product, ensuring there are no missed steps or ‘walk-arounds.’ This is a live system so process and quality data constantly are updated and provided to the operators and engineers as products run on any one of the four 2production lines JEMS has, allowing for constant process monitoring and immediate intervention when required. As previously discussed, all parameters for the screen printing process for all the different printed circuit board assemblies (PCBAs) are defined and provided in Aegis. Many industry studies show that 60-80 percent of surface mount solder joint defects are due to the issues associated with screen printing. The Automatic Pin Guidance (APG) function offered by EKRA X4 screen printers has significantly reduced insufficient and open solder defects at JEMS that are caused by inappropriate printer setup for doublesided assemblies. These screen printers incorporate a vision-mounted laser pointing system and the support pin locations can be taught easily via the vision system. According to the comparison study result of EKRA APG implementation at JEMS, the insufficient and open solder defect appearances on the boards were reduced by 55 percent compared to the boards set up without APG. Additionally, this repeatable process helps engineers discover the true root cause of the printing defects for repeat builds. To validate the screen printing process, JEMS installed a CyberOptics fully automated 3D solder paste inspection (SPI) system on every surface mount (SM) line. “Our belief is that this is one of the most crucial processes of the line because we are checking not only registration of paste but, more importantly, the volume of the paste deposited on each and every pad on the PCB,” said Walker. This machine provides instantaneous feedback to the line operators if there is any deviation of the printing process that guarantees that when a part is placed on a PCB, the correct amount of solder paste is there for a reliable solder joint after reflow or, if not, the board is pulled offline for paste removal cleaning, and the correction/ adjustments are made to the screen printer. This is critical when building highly complex products that use highdensity BGAs, microBGAs, PoP, QFNs, LGAs and 01005 devices to avoid assemblies going offline and the need to rework them due to poor solder joints. Once the board passes through the SPI system, all devices are placed using a Juki inline system. JEMS has four lines with a combination of 12 machines total. Walker said that buying the new Juki systems and not purchasing used legacy SM equipment allows the company to confidently place any of the devices previously listed at production-level speeds and with ±0.03 mm accuracy. The Juki machines also are equipped with feeder trolley carts such that they allow for quick product-to-product changeover. To guarantee that the correct parts are loaded on the respective feeders at initial feeder set up, JEMS performs an automated offline verification of all the feeders on each cart. Once the trolley cart is inserted into the machine, there is a validation program through Cogiscan in conjunction with Juki to ensure that the right component/ feeder is the right location for the PCBA placement program. Another critical in-process check is the company’s automated optical inspection (AOI) systems and it has one on each of the assembly lines and completes a 100 percent inspection of every single board that is assembled. “We place so much emphasis on AOI that depending upon the PCBA being built, this machine potentially gates the entire SM line,” added Walker. Nordson YESTECH’s advanced 5-megapixel color camera imaging technology offers highspeed PCB inspection with exceptional defect coverage. With one top down viewing camera 3and four side viewing cameras, the FX Series inspects solder joints, lead banks and verifies correct part value and placement, enabling JEMS to improve quality and increase throughput. Programming the FX Series is fast and intuitive. Operators typically take less than 30 minutes to create a complete inspection program including solder inspection. Advanced Fusion Lighting™ and 5 megapixel image processing technology integrate several techniques, including color inspection, normalized correlation and rule-based algorithms, to provide complete inspection coverage with an extremely low false failure rate. Walker said that these features make the FX AOI system ideal for JEMS, and the performance value of the machines is outstanding. Another critical process step JEMS performs in-house to validate and improve quality is automated 3D X-ray. While the company does 100 percent AOI on every board it assembles, the machine cannot inspect for what it cannot see so devices such as BGAs can only be validated for correct part and alignment at this step. The solder joints themselves must be inspected by using X-ray, which JEMS also performs on 100 percent of the products it assembles. JEMS uses two of ViTrox’s automated X-ray (AXI) systems and views them as “best in class” for production-level, fully automated X-ray capabilities. The V810 state-of-the-art technology is based on digital tomosynthesis methodology and the use of proprietary Hybrid Auto Focus technology that enables the system to intelligently focus on the desired z-height. This is accomplished without any mechanical movement from an X-ray source or stage that can help to significantly reduce the measurement uncertainty of the system. The X-ray system uses advanced package inspection capability that includes three layers for PoP, LGA and pin-in-paste. The test coverage of the V810 Series2 XXL is improved through nonlinear reconstruction technology that enables better inspection of highly shaded parts such as connectors and power transistors. The new flood-fill voiding algorithm enhances the accuracy and various detection types for voiding including barrel fill for through-hole devices. Most of JEMS customers have highcomplexity products, high-mix, low- to medium-volume production requirements so the company uses only the most advanced equipment and systems to provide continuous monitoring, verification and feedback of 100 percent of our process steps regardless of board quantity (prototypes through production). This has allowed the company to continually target customers with complex assemblies and at same time improve its quality significantly so that it has average first pass yields of greater than 96 percent and average defects per million opportunity (DPMO) rates of less than 70, which at the end of the day, allows JEMS to build more efficiently and to have optimal utilization of its manufacturing facility. For more information visit: www.javadems.com

0

Start typing and press Enter to search