STMicroelectronics Inc. (ST, Geneva, Switzerland) announced the capability to manufacture ball grid array (BGA) packages 1.6 mm high that contain as many as eight stacked memory chips. The same technology is also being used to pack two memory dies into a 0.8 mm thick ultra-thin fine-pitch BGA (UFBGA). Devices produced using the new technology will be suitable for more memory in smaller volume, for phones, cameras and PDAs.
The multi-chip package (MCP) devices containing between two and four chips are already widely used in products such as mobile phones where space is at a premium. By literally stacking two or more chips on top of each other, the space required on the printed circuit board is the same as would be needed for a single chip – and because memory chips use many common signals, such as address and data bus lines, the number of connections between the package and the board is almost the same.
