i2a Technologies' stacked-die packaging is used to dramatically increase packaging density and to put multi-chip functionality into a single IC package

Stacked-die packaging allows for very efficient use of mother-board real estate, reducing size and weight, as well as contributing to system level cost reduction. The technology also enables the flexibility of combining custom chips with off-the-shelf devices to further reduce total systems cost.

Stacked-die packages are often used in products requiring increased memory density and performance while reducing package size. Portable electronics products such as cell phones, PDAs, camcorders and other wireless consumer systems can benefit from the combination of multi-chip function and small footprint.

i2a offers three basic stacked die versions of wire bonded packages, (a) pyramid stacked die where smaller die are placed on top of larger die, (b) same size die with a silicon spacer placed between the two die, and (c) die with overhang where rectangular die are placed at 90 degrees on top of each other. The die are thinned to 8-10 mils in order to achieve maximum package heights of 1.4mm an 1.2mm.  Stacked-die packages with three and more stacked chips are also available.  Below are illustrations of the basic two-die stack versions:

Pyramid stack configuration

Same-die stack configuration

Overhang cross stack configuration