Highly efficient InGaN/GaN blue LED on 8-inch Si (111) substrate

We have grown LED structures on top of a robust n-type GaN template on 8-inch diameter silicon substrates achieving both a low dislocation density and a 7 um-thick template without crack even at a sufficient Si doping condition. Such high crystalline quality of n-GaN templates on Si were obtained by optimizing combination of stress compensation layers and dislocation reduction layers. Wafer bowing of LED structures were well controlled and measured below 20 mu m and the warpage of LED on Si substrate was found to strongly depend on initial bowing of 8-inch Si substrates. The full-width at half-maximum (FWHM) values of GaN (0002) and (10-12) omega-rocking curves of LED samples grown on 8-inch Si substrates were 220 and 320 arcsec. The difference between minimum and maximum of FWHM GaN (0002) was 40 arcsec. The dislocation densities were measured about 2 similar to 3x10(8)/cm(2) by atomic force microscopy (AFM) after in-situ SiH4 and NH3 treatment. The measured quasi internal quantum efficiency of 8-inch InGaN/GaN LED was similar to 90% with excitation power and temperature-dependent photoluminescence method. Under the un-encapsulated measurement condition of vertical InGaN/GaN LED grown on 8-inch Si substrate, the overall output power of the 1.4x1.4 mm(2) chips representing a median performance exceeded 484 mW with the forward voltage of 3.2 V at the driving current of 350 mA.