Claiming a revolution for the semiconductor industry, Motorola announced Tuesday a breakthrough in materials science that it says will be the key to a new class of high-performance chips. The innovation should pave the way for faster and less expensive devices, from 3G (third-generation) mobile handsets with streaming video, to automotive collision-avoidance systems, the company said.
Motorola researchers claim that they have succeeded in combining for the first time standard silicon semiconductor technology with compound semiconductors known as III-V materials -- so called because of their position in the third and fifth columns of the Periodic Table of Elements.
The compounds, which include gallium arsenide (GaAs) and indium phosphate (InP), have superior electrical and optical characteristics allowing for higher switching speeds and power efficiency, but have so far been of limited practical usefulness. By contrast, silicon, the workhorse of the semiconductor industry, is cheap but has its own limitations, including its poor ability to emit light and hence the difficulty of integrating silicon chips into laser or fibre-optic applications.
"Gallium arsenide and indium phosphate are materials which the industry has talked about for a long time, and which can handle the greater demand of these next-generation devices, but the problem is because they are brittle and have limitations of their own, people haven't been able to produce them in very high quantities, and they were expensive," a spokesman said.
The new process, developed by a team headed by Motorola scientist Jamal Ramdani, allows a thin layer of a III-V compound to be grown atop a silicon substrate, "so that a silicon chip becomes silicon plus. Then you can reduce the space required and reduce the cost. That is basically a challenge that the industry has tried to solve for a long time," the spokesman said.
The researchers were able to create GaAs-on-silicon wafers up to 30 centimeters in diameter, build power amplifiers from those wafers and demonstrate them in mobile phones, Motorola said.
A practical application of III-V semiconductor materials could mean a new wave of faster and cheaper applications, the spokesman said -- even all-optical switches, which he called "a holy grail" for the industry.