Monday, January 29, 2007

Intel, IBM Overhaul Material for Next-Generation Microprocessor

Both companies modify transistor materials to make smaller, faster, more energy-efficient processors.

By Kate Greene

An image of Intel’s static random access memory (SRAM) chip--containing more than one billion transistors--which is built from new materials, the company announced today. Separately, IBM and Intel announced new chip materials to help improve computing performance for next-generation microprocessors. Credit: Intel

On Saturday, Intel and IBM separately announced a new type of transistor material that the companies say will lead to smaller chips, increased computing performance, and more energy-efficient computers. Both chip makers have plans to integrate the new material into the next manufacturing line of chips--known as the 45-nanometer generation--within a year. Ultimately, this advance should make computers better at playing video games, editing movies, and performing other processor-intense tasks.

Intel, known for its personal-computer chips, has also announced that the new chips will appear in its next generation of "dual core" and "quad core" computers and servers, which are expected to be in production at the end of this year. IBM, well-known for its servers and high-performance computing systems, expects that products featuring its new chips will ship by early 2008.

Historically, the performance of microprocessors has doubled every two years, following a trend known as Moore's Law. Performance has increased thanks to chip fabrication technology that has let transistors shrink with each generation, either allowing more transistors to be packed on a chip or allowing the chips to be made smaller. Currently, most computer and server microprocessors are made using what is known as a 65-nanometer process. The next generation of transistors will be made smaller using a 45-nanometer process. However, the companies' new materials will provide this generation of chip with a performance boost that wouldn't be possible otherwise.

One of the material changes will be in an important transistor component called the gate dielectric. This component helps control the flow of electrons, which turn the transistor on or off. For decades, the gate dielectric has been made of an insulating material called silicon dioxide. However, as transistors have shrunk, the layer of silicon dioxide has needed to become thinner. This poses a problem, however, because a thin layer of silicon dioxide lets electrical current leak through it, producing excess heat and resulting in poor device performance.

IBM and Intel found that a material called high-k produces the same benefits of silicon dioxide, but it can do so in a thicker layer. The material is based on the element hafnium, and both companies claim that it significantly reduces the amount of current leakage.

In addition to having to replace the gate dielectric, both companies were forced to rethink the type of material to use for the gate itself--the transistor component that ultimately turns a transistor on and off. Traditionally, gates have been made of polysilicon, a less structured form of crystalline silicon, which is used in the transistor. But in order to make the gate compatible with the new gate dielectric, Intel and IBM replaced polysilicon with a metal whose name neither company will disclose at this time.