New 3-D Transistors Promising Future Chips,Lighter Laptops

Researchers from Purdue and Harvard universities have created a new type of transistor made from a material that could replace silicon and have a 3-D structure instead of conventional flat computer chips. The approach could enable engineers to build faster, more compact and efficient integrated circuits and lighter laptops that generate less heat than today's. The transistors contain tiny nanowires made not of silicon, like conventional transistors, but from a material called indium-gallium-arsenide.

The device was created using a so-called "top-down" method, which is akin to industrial processes to precisely etch and position components in transistors. Because the approach is compatible with conventional manufacturing processes, it is promising for adoption by industry, said Peide "Peter" Ye, a professor of electrical and computer engineering at Purdue.

A new generation of silicon computer chips, due to debut in 2012, will contain transistors having a vertical structure instead of a conventional flat design. However, because silicon has a limited "electron mobility" -- how fast electrons flow -- other materials will likely be needed soon to continue advancing transistors with this 3-D approach, Ye said.

Indium-gallium-arsenide is among several promising semiconductors being studied to replace silicon. Such semiconductors are called III-V materials because they combine elements from the third and fifth groups of the periodic table.

"Industry and academia are racing to develop transistors from the III-V materials," Ye said. "Here, we have made the world's first 3-D gate-all-around transistor on much higher-mobility material than silicon, the indium-gallium-arsenide."