IBM Creates Self-Assembling Chips Modeled After Nature

IBM is taking a cue from nature to build the next generation computer chips. IBM borrowed the natural pattern-creating process that forms seashells, snowflakes and tooth enamel to help create next-generation chips. The method form trillions of holes to create vacuums as insulation around the miles of nano-scale wires packed next to each other inside the chip.

Today, chips are manufactured with copper wiring surrounded by an insulator, which involves using a mask to create circuit patterns by beaming light through the mask and later chemically removing the parts that are not needed.

The new technique skips the masking and light-etching process, opting to use a vacuum gap – misleadingly referred to as airgaps – as an insulator. IBM scientists discovered the right mix of compounds, which they poured onto a silicon wafer with the wired chip patterns, and then baked it.

This concept occurs in nature for the formation of snowflakes, seashells and tooth enamel. The major difference is that IBM has been able to direct the self-assembly process to form trillions of holes that are all similar, while the processes that occur in nature are all unique.

This process provides the right environment for the compounds to assemble in a directed manner, creating trillions of uniform, nano-scale holes across an entire 300 millimeter wafer. These holes are just 20 nanometers in diameter, up to five times smaller than would be possible using today’s most advanced lithography technique.

Once the holes are formed, the carbon silicate glass is removed, creating a vacuum between the wires allowing the electrical signals to either flow 35 percent faster, or to consume 15 percent less energy. A vacuum is believed to be the ultimate insulator for what is known as wiring capacitance, which occurs when two conductors, in this case adjacent wires on a chip, sap or siphon electrical energy from one another, generating undesirable heat and slowing the speed at which data can move through a chip.

“This is the first time anyone has proven the ability to synthesize mass quantities of these self-assembled polymers and integrate them into an existing manufacturing process with great yield results,” said Dan Edelstein, chief scientist of the self-assembly airgap project. “By moving self assembly from the lab to the fab, we are able to make chips that are smaller, faster and consume less power than existing materials and design architectures allow.”

IBM boasts that its self-assembly nanotechnology process provide the equivalent of two generations of Moore's Law wiring performance improvements in a single step. The self-assembly process already has been integrated with IBM manufacturing line in East Fishkill, New York and is expected to be fully incorporated in IBM’s manufacturing lines and used in chips in 2009. Furthermore, this new technology can be incorporated into any standard CMOS manufacturing line, without disruption or new tooling.

The chips will be used in IBM's server product lines and thereafter for chips IBM builds for other companies, for example, the Cell Broadband Engine found in the PlayStation 3 and various servers.

Over the past few months, IBM has had a number of major chip technology announcements and demonstrations that the company claims will extend Moore’s Law. In December, IBM announced the first 45nm chips using immersion lithography and ultra-low-K interconnect dielectrics.

In January, IBM announced high-k metal gate, which substitutes a new material into a critical portion of the transistor that controls its primary on/off switching function. In February, IBM revealed its on-chip memory technology that features the fastest access times ever recorded in eDRAM. Then in March, IBM unveiled a prototype optical transceiver chipset capable of reaching speeds at least eight-times faster than optical components available today. More recently, IBM developed a new chip stacking technology that shortens wire lengths inside chips up to 1000 times.