The package, which won't start shipping until 2007, is a twist on thealready being produced by Samsung, Intel and others. In these packages, memory chips are stacked on top of each other instead of sitting side by side. This saves on motherboard space and allows cell phone designers, MP3 makers and others to create smaller devices.
In these multichip modules, the different chips are actually in their own separate enclosures within the packages and communicate with each other and the rest of the components through wires connected to small metal balls studding the outside of their individual enclosures.
The new package, called a wafer-level processed stack package, uses a technology called, or TSVs. With TSVs, a wire runs directly from the silicon in one chip to another, eliminating the need for much of the additional packaging. This cuts down space even further. (Other manufacturers are working on TSVs as well.)
Samsung's WSP can contain eight chips stacked up on top of each other. The prototype, for instance, contains eight 2GB flash chips for a total of 16GB of memory. It is only 0.56 millimeters high. The WSP will first be used in flash memory cards but later will contain different combinations of chips. A single package, for instance, could contain DRAM, the kind of memory found in PCs and processors, as well as flash.