Hydrogenated amorphous silicon carbide double graded-gap p-i-n thin-film light-emitting diodes

Hydrogenated amorphous silicon carbide (a-SiC:H) p-i-n thin-film light-emitting diodes (TFLEDs) with graded p/sup +/-i and i-n/sup +/ junctions have been proposed and fabricated successfully on an indium-tin-oxide (ITO)-coated glass. An orange TFLED reveals a brightness of 207 cd/m/sup 2/ at an injection current density of 500 mA/cm/sup 2/. This significant increase of brightness could be ascribed to the combined effect of reduced interface states by using the graded-gap junctions, lower contact resistance due to post-metallization annealing, and higher optical gaps of the doped layers.>