IBM Develops Chip Stacking Technology

After a decade of research, IBM has developed a new technology that allows for the creation of 3D computer chips. The new development will greatly shorten the amount of wiring needed in a chip, and will allow for roughly 100 times more connections. All of this means that we will see radically faster computers in the relatively near future. IBM says it expects production to begin on the first of the chips made with this technology next year.

Microchips, essentially, are incredibly complicated circuits printed onto tiny pieces of silicon. A circuit which, containing thousands of resistors and transistors, would occupy a piece of circuit board several feet square, can be printed onto a chip smaller than a pencil eraser. Needless to say, this technology dramatically cuts down on cost and size, and greatly improves efficiency. In fact, it has made possible the entire realm of modern electronics as we know it. However, microchips have one limitation: they are flat.

The fact that microchips can only exist in two dimensions limits the complexity of the circuits that they can hold. Passages cannot pass over each other, and a great deal of space is occupied by long contacts. It has long been known that by eliminating this limitation, the realm of possible microchips would expand exponentially. To this end, IBM began a project to develop this technology about ten years ago.

Their new process, essentially, has allowed them to stack multiple layers of microchips, much the way floors are stacked in buildings. Previously, this was rendered impossible by the lack of a technology to connect upper and lower levels. With this new technology, about which very little has been released, circuits on different layers could be connected in a practical and cost effective manner, increasing the number of possible pathways by a factor of 100, and decreasing the total distance traveled by electricity by a factor of 1000. Although you wouldn't necessarily come to this conclusion immediately, connections are the major limiting factor in microchips. In fact, the microchip as you see it, in fact an integrated circuit encapsulated in a small square of black plastic, is about 95% wiring. Tiny gold pathways for electricity, connecting the chip to the legs, account for almost all the space in the chip. By reducing the amount of wiring that is needed within a chip, circuits will be able to run much faster.

The new technology, which is already being implemented, is expected to be used in wireless communications, faster processors, and more powerful supercomputers. We will likely see the first products made with these new chips about a year from now.
Sources:
http://www.ibm.com
http://www.sciencedaily.com/releases/2007/04/070412132140.htm