September 23, 2003 – STMicroelectronics says it has made “significant advances” in developing light-emitting silicon technology with properties rivalling those of compound semiconductor materials.
Silicon has been used to detect light signals in digital camera chips, but other materials such as indium, gallium, and arsenic have better light-emitting properties.
Last year STMicro developed silicon technology with double the light-emitting capabilities to be more in line with compound semiconductors’ efficiencies, but at a lower manufacturing cost.
Now, the company says it has increased the external quantum efficiency of its prototype devices by 150%, and boosted the maximum emitted power to more than 1mW/mm<+>2<+> — a 50x increase in output.
“It will be possible to increase this performance by at least another order of magnitude,” according to Salvo Coffa, R&D research director of STMicro’s soft computing, Si-optics, and post-silicon technologies group.
STMicro plans to develop new chips to integrate three functions of light emission, light waveguides, and light detectors onto a single silicon chip, manufactured at low cost on high-volume production lines. Future applications include use in optocouplers, displays, and solid-state illumination.