Effects of Ag/indium tin oxide contact to a SiC doping layer on performance of Si nanocrystal light-emitting diodes

We report on the effects of a very thin Ag (2.5nm) interlayer between the indium tin oxide (ITO) current spreading layer and a SiC doping layer on silicon nanocrystals (nc-Si) embedded in silicon nitride film on the electrical and optical performance of the light-emitting diodes (LEDs). The forward voltage at a current of 20mA of the nc-Si LED with a Ag interlayer was decreased by 2.5V compared to that of the nc-Si LED without one due to the decrease in the contact resistance. In addition, the light output power of the nc-Si LED with a Ag interlayer was also enhanced by 40%. This result strongly indicates that the Ag/ITO contact scheme can serve as a highly promising contact scheme to a SiC film for the realization of the nc-Si LEDs with a high efficiency.