Original URL: http://www.theregister.co.uk/2006/11/01/samsung_16-chip_stack_tech/

Samsung squashes 16 Flash chips into one

Multi-die stacking enhanced for cheaper MP3 players

By Tony Smith

Posted in Hardware, 1st November 2006 12:08 GMT

Samsung has worked out how to stack up to 16 memory dies in a single package, allowing a standard-sized chip to contain rather more storage capacity than is currently the case. A chip that might have once held 10GB of Flash memory can now hold 16GB.

Samsung's technique is to narrow the thickness of each memory wafer to 30µm, down from the 45µm thickness the wafers in the company's current ten-chip stacking process. The thinner wafers need special handling, so Samsung said it cuts them using lasers rather than the mechanical saws more commonly used for this kind of thing.

samsung multi-die chip package
Multi-die stacking then (left) and now (right)...

The new technique uses less adhesive between each chip - the glue layer's 20µm, compared to 60µm in the ten-chip process. That means there's less space between wafers for connecting wires. To get around that, Samsung said it stacks the wafers slightly off-axis to create a gap between the edge of the lower die and the one above - room enough to connect up the wiring.

Samsung didn't say when it will be delivering chips based on the new die-stacking technique. ®