Pin-gate molding structures are said to provide superior quality, reliability and performance, and can be less expensive than traditional corner gate molding. Amkor’s PGM process is designed with a JEDEC-compliant larger mold cap which has a number of benefits, including allowing the routing of active traces and vias within the mold cap dimensions, improving protection from solder mask cracking, and facilitating larger die sizes in the same form factor. In addition, Amkor’s PGM PBGA uses a package saw singulation process which produces a smoother edge on the package, reducing the potential for binding in the test socket and shipping tray, and thus delivering higher yields.
PGM is also a more cost-effective PBGA structure as it uses higher density substrates and smaller diameter wire than traditional corner gate molding. Gold wire diameter can be reduced by over 50% down to 0.5 millimeters. Copper wire diameters can also be reduced significantly. These capabilities also extend the usefulness of wirebonding to smaller silicon nodes. With PGM, wirebonding can now be used down to 28 nm.
The white paper describes the package, the process, reasons for the change and the current state of volume production.