Raymond van As, project engineer for Philips' CFT group, knew that no matter the sophistication of his analytical tools or test methods used to achieve a Six Sigma-capable sawing process, he would need a more superior machine than the existing sawing equipment at the company's Manila factory. "The Manila factory's sawing machines were already operating at levels beyond their normal capacity. We needed more power from the saw," he explains.
The SOD110 high-performance package uses Philips' proprietary V-packTM technology and outperforms both mini-MELF glass and plastic-packaged MELF products. The SOD110's rectangular-shaped, stress-free ceramic package is easier to handle than cylindrical MELFs, contributing to its superior pick-and-place performance and reliability during mass board assembly. As a result, the product is in high demand.
CFT originally designed and delivered to the Manila factory a volume sawing process that consisted of 50 ceramic bars precisely mounted to a two-sided frame or loading rack, with each bar containing 149 products. Typical dimensions of the separated products are 1.50 x 1.25 x 2.20 mm. Philips' unique cutting approach consisted of 50 diamond blades and adjoining pitch spacing components precisely assembled on a gang arbor. After only three passes of the gang, the sawing process was complete, yielding a total 7450 products per load run.
According to Jimmy Bonifacio, manager of process engineering at PSPI, throughput at the Manila factory was only limited by the existing saws' inability to withstand increased cutting load conditions when attempting higher feed rates. "We were experiencing a bottleneck in our gang sawing process. We knew we could easily invest in a new machine, but we also wanted to innovate the process by improving cutting efficiency. We needed a cutting-edge technology to achieve this," he says.
The micro slicing system uses ultra-high precision, anti-friction linear bearings for all three axes of travel. Indexing accuracy is up to ñ0.00001 in. (ñ0.25 æm), which is consistent with Philips' minimum 1.33 Cpk process capability requirement.
The system's bridge-type construction and a base made of heavily ribbed cast iron provided the stability and rigidity the CFT engineers were looking for. The precision-feed X-slide and the indexing Y-slide mounted on a 5500-lb (2500-Kg) laboratory-grade granite block and kinematically suspended on three-point adjustable supports ensured distortion-free alignment of the datum plane in relation to the spindle and Z-axis.
These structural features would ultimately prove beneficial to eliminating side loading of the blades at the higher table feed rates desired for the high-speed sawing process. According to CFT engineers, the stiffness of the micro slicing system's dual-supported 10 hp mechanical bearing spindle arrangement, along with the machine's reliability and fixed tabletop in relation to the spindle system, were the key features that led them to select the system.
"The system was the perfect fit of process to equipment," says van As.
As CFT launched into the alpha phase of the IPD, it was readily apparent to the engineers assigned to the project that many of the risks identified in the feasibility phase were minimized or eliminated with the implementation of the micro slicing system. Product cost reduction ideas, such as saving material cost by increasing the number of products per ceramic bar from 150 to 175, were added to the deliverables. CFT immediately set out to develop a custom blade type that would:
Results of CFT's development work and selection of the micro slicing system proved highly successful and yielded the following improvements at the Manila factory:
For more information about the micro slicing system, contact Veeco Slider Process Equipment Inc. at 2226 Goodyear Ave., Ventura, CA 93003-7750; (805) 644-9681; fax (805) 644-3541; e-mail firstname.lastname@example.org ; or visit http://www.veeco.com .
More information about Philips Semiconductors can be found at http://www.semiconductors.philips.com .