Researchers at Rensselaer Polytechnic Institute have developed a new method for manufacturing green-colored light-emitting diodes (LEDs) with greatly enhanced light output. The research team, led by Christian Wetzel, professor of physics and the Wellfleet Constellation Professor of Future Chips at Rensselaer, etched a nanoscale pattern at the interface between the LED's sapphire base and the layer of gallium nitride (GaN) that gives the LED its green color. Overall, the new technique results in green LEDs with significant enhancements in light extraction, internal efficiency and light output.
This research is supported in part by the National Science Foundation Smart Lighting Engineering Research Center (grant EEC 08-12056). To read more about this research, see the Rensselaer news release Energy@Rensselaer: Zeroing in on the Elusive Green LED.
(Date of Image: September 2009)