First Three-Chip Stacked CSP Developed
-- Semiconductor International, 1/1/2000
Sharp Electronics (Hamburg, Germany) claims to have developed the world's first three-chip stacked chip-sized package. It is intended mainly for the cellular telephone market and the information and communications handheld terminal market. Mass production began in August, and a production system with capability of 1 M chips/month is expected to be available by first quarter of 2000.The three-chip stacked CSP uses a Sharp-developed technology that uses special thin silicon wafers with die and wire bonding. They are specially modified for the purpose. The three chips are stacked in a single package, requiring less space to mount the chip packages (see Figure). The CSP products also can be lighter in weight. Package height doesn't exceed 1.4 mm, so it may replace existing two-chip stacked designs, which Sharp has been delivering since April 1998.
This stacking technique also has been applied in next-generation compound memory products with three separate memory chips in one package. Other products include a memory controller together with a flash ROM and a normal RAM chip, as well as a new advanced system-on-a-chip IC device that integrates a cellular telephone control IC, flash memory and SRAM in one package.
"In addition to saving space in small appliances the three-in-one' design will make circuits more reliable and allow faster operation due to shorter connection wires," said Stefan Hauf, product marketing manager of the microelectronics division at Sharp Electronics Europe. "Weight and mounting space are estimated both to be cut in half when compared with three discrete chips in separate packages."
- Brian Dance
