Aug 19, 2009 
Unlike alternative methods that employ serial approaches for placement of solder balls, the parallel print process of DirEKt Ball Placement allows for unmatched, repeatable accuracy and exceptionally fast cycle times which are completely independent of I/O count. While these statistics are arguably impressive and consistent with requirements for next-generation wafer-level CSP devices, DEK is also upholding its pledge to continuously enhance DirEKt Ball Placement capability.
As part of this commitment, the mass imaging leader has designed the Galaxy Thin Wafer System, a high-accuracy print platform capable of meeting the demands of thinned wafer processes and precision microsphere ball placement. The system’s newly engineered wafer pallet, which is flat to less than 10µm with the ability to accommodate wafers as large as 300mm and as thin as 75µm, is the foundation for advancing sphere placement processes to the next-generation.
“While we have achieved 99.99% repeatable first pass yield with 200µm balls at 300µm pitch in high-volume production, even more highly miniaturized spheres have been successfully placed in a lab environment, with work ongoing to prove the process in the field,” says DEK’s Semicon and Alternative Applications Manager, David Foggie. “Our active development program to deliver sub-100µm microsphere placement is well underway, with early results delivering an exceptionally high first-pass yield”
The DirEKt Ball Placement system utilizes two side-by-side print platforms, with the first system using flux imaging technology to precisely deposit flux at each interconnect site. The second printer, a Galaxy Thin Wafer System equipped with an advanced enclosed sphere transfer head capable of holding up to 100 million solder balls, then accurately seats each ball into the flux. Enabled by the enhanced stability and security of the Galaxy Thin Wafer System, DEK’s DirEKt Ball Placement technology can process as many as 45 wafers per hour.
“High UPH microsphere placement is clearly the cost-effective way forward for wafer-level CSP manufacture,” concludes Foggie. “DEK’s DirEKt Ball Placement system delivers the precision, repeatability, platform flexibility and low cost of ownership commitment necessary for advancement of this critical packaging technology.”
About DEK
DEK is a global provider of advanced materials deposition technologies and support solutions including printing equipment platforms, stencils, precision screens and mass imaging processes used across a wide range of applications in electronics pre-placement subassembly, semiconductor wafer manufacture, and alternative energy component production. For more information, visit DEK at http://www.dek.com.
