Three Dimensional Memory from Samsung

On the "merry-go-round" of the computer industry, there are a lot of ideas being swung back and forth between manufacturers; sometimes, there are people that get upset about somebody else using their ideas, so they put up a copyright on them. Others, on the other hand, are more than thankful that somebody is using their technology, because it will advance faster and to a higher level and also it will get them a lot of money in the process.

Such is the case of Samsung, they are both creators and users of ideas, one of which, their latest, is closely related to the SF domain, more than the computer industry, or maybe not. Based on a revolutionary idea IBM came up with, they have also made some progress and are now announcing "the first all-DRAM stacked memory package using 'through silicon via' (TSV) technology". This memory circuitry takes the concept of side-by-side layered PCB's, and takes it into the third dimension, by making the connections between components in a 3D environment. By doing so, they are reducing the time needed for electrons to pass from one chip to the other and allowing packages to be manufactured on smaller sizes, that consume less power and, of course, are faster.

Samsung's manufacturing process has devised a Wafer-level-processed Staked Package (WSP), which in term is made out of four 512Mb DDR2 chips. By using the TSV process, Samsung can create a 4GB memory module based on the WSP technology. To overcome some of the technological problems encountered with the manufacturing process, such as the performance-slow-down effect caused by the redistribution layer, Samsung has placed the TSV into an aluminum pad. Regarding the wafer itself, the size of it and the thin profile have the tendency of bending the wafer; Samsung's "wafer-thinning" technology has been used to reduce the thin-die-cutting process.

Tae-Gyeong Chung, vice president, Interconnect Technology Development Team, Memory Division, Samsung Electronics said: "The innovative TSV-based MCP (multi-chip package) stacking technology offers next-generation packaging solution that will accommodate the ever-growing demand for smaller-sized, high-speed, high-density memory. In addition, the performance advancements achieved by our WSP technology can be utilized in many diverse combinations of semiconductor packaging, such as system-in-package solutions that combine logic with memory".