HIGH-BRIGHTNESS BLUE-GREEN LIGHT-EMITTING-DIODES ON ZNSE SUBSTRATES

High-brightness blue and green light-emitting diodes (LEDs) are produced based on homoepitaxial films grown by molecular beam epitaxy (MBE) on high quality ZnSe substrates. The substrates are grown by the Eagle-Picher, seeded physical vapor transport (SPVT(TM)) technique. The substrates are twin-free and contain no low-angle grain boundaries. Double-crystal X-ray diffraction rocking curve studies yield a FWHM [400] = 11'' to 16'', indicating a crystal quality comparable to that of GaAs substrates. The blue LEDs produce 327 mu W (10 mA, 3.2 V), with the light output sharply peaked at 489 nm, and exhibit an external quantum efficiency of 1.3%. The green LEDs produce 1.3 mW (10 mA; 3.2 V) peaked at 512 nm, corresponding to an external quantum efficiency of 5.3%.