Intel's transistor redesign ushers in 'new era' of technology

Computerworld - To make the jump from 65 nanometer to 45 nanometer processor technology, Intel Corp. redesigned the transistor, an advancement that one analyst said will usher in a new era in technology.

The normally little-talked-about transistor is the building block for the processor. And Intel changed out critical materials in its redesign, trading polysilicon for a metal gate and using hafnium oxide as an insulator. The better insulation means there's less energy leakage, and the metal gate is a better conductor, moving the current through faster.

All of that enabled Intel to make the move from 65nm chips to the 45nm Penryn family of processors while reducing heat output and energy consumption and without inducing major energy leakage.

It's a redesign that Intel boasts will extend Moore's Law by another 10 years. The 40-year-old prediction by Gordon Moore holds that the number of transistors on a chip doubles about every two years. However, some observers had predicted that leakage and energy consumption looked like significant roadblocks to the law continuing to hold true.

A new design was needed. And while companies like IBM and Advanced Micro Devices Inc. all are working on the same problem, Intel was the first one to find an answer.

And some analysts say the new transistor design is one of the most significant technological advances in the past several decades. Time magazine agreed, naming it the one of the best inventions of 2007, trailing only Apple Inc.'s iPhone.

"Figuring this out was a major accomplishment," said Dean Freeman, an analyst at Gartner Inc. "It's an evolutionary advancement that needed to take place for the industry to continue to move forward. It's something people have been working on for over 10 years. We've moved away from polysilicon dioxide gate technology and we've moved into metal gate. It's a new era in technology."

The transistor is made up of switches. As switches are turned on or off, current either flows or stops. By applying power to a gate, which has traditionally been made of polysilicon, current is allowed to flow, explained Freeman. As transistors shrink, going from 90nm to 65nm and now to 45nm, the gate shrinks in size and length as well. That means the polysilicon must become thinner and thinner. The problem was that thin polysilicon allows electrons to tunnel through, causing energy leakage. The more energy that uselessly leaks out, the more power the chip needs to function.

Freeman noted that if the chips built with polysilicon got any smaller, they would eventually need a virtual power plant to fuel them.

Now the chips use a metal gate that sits on top of an insulator made up of hafnium-based "high-k." Intel has refused to say what the metal gate is made up of.