Improved Lead Carrier Substrate Enables "Super QFN" Chip Package

EoPlex Technologies Inc.'s xLC substrate, for Quad Flat No Lead semiconductor packages(QFNs), enables packaging companies to produce a "super QFN" with hundreds of leads and multiple rows at a lower cost than conventional packages.

QFNs are the fastest growing packaging segment; however, they cannot be used in many applications due to the limitations imposed by the metal leadframe that is used to build them. The most critical limitation is that the leadframe prevents multi-row and high lead count designs. This makes it impossible for low cost QFN packages to replace more expensive packages like fine-pitch BGA. The leadframe also makes QFNs bigger than necessary, adds extra metal which reduces electrical performance, requires expensive polyimide tape and can slow down process steps like dicing and testing.

The EoPlex xLC substrate is a sintered metal array of wire bond and die attach pads delivered on a temporary thin metal strip, referred to as a lead carrier. The product is designed to be a direct replacement for the leadframe and is completely compatible with all QFN processing. With EoPlex xLC, packages can be made with as many rows as needed with hundreds of leads. All of the excess metal in the conventional leadframe is eliminated, along with the expensive polyimide tape. Unlike leadframes and other processes that require etching and plating chemicals, xLC production is based on sintering and is a green process.

Arthur L. Chait, CEO of EoPlex, said, "Our process uses space very efficiently and has no wasted metal. This allows us to place up to 50 percent more package-sites on each strip, resulting in a price per package-site that is 20-30 percent less than leadframes. This lower initial price plus the process cost savings that xLC gives our customers the lowest total cost of ownership. This product makes it easy to design QFN packages, with very high lead counts, that can replace more expensive packages and yet still be low enough in cost to replace commodity QFNs. Truly a 'super QFN'."

EoPlex Technologies