Researchers report InGaN/GaN lasers on silicon
The laser was described during a presentation at the International Workshop on Nitride Semiconductors in Aachen, Germany. The device features a wavelength centered on 447 nm and a maximum operating temperature of 420 K. A low threshold current allows the laser to attain a power density of 270 kW/cm2 and an output power of 8-10 W.
Silicon wafers are available in diameters of up to 12 inches, and potentially offer a lower cost platform for compound semiconductor-based devices. InGaN-based lasers and LEDs are currently manufactured on expensive, smaller diameter (e.g. 2 to 4-inch) SiC and sapphire wafers. These results are similar to lasers grown on sapphire and SiC substrates, says the group.
A number of other companies have reported GaN device structure grown on silicon, including Nitronex, the University of Magdeburg, Germany, and the Japanese company Sanken. In common with SiC, silicon wafers offer high thermal conductivity and are conducting, which allows simplified LED manufacturing compared to sapphire wafers.
