Enhancement in optical and electrical efficiency of a Si nanocrystal light-emitting diode by indium tin oxide nanowires

C. Huh, T.-Y. Kim, B.-J. Park, E.-H. Jang, S.-H. Kim
Electronics and Telecommunications Research Institute, KR

Keywords: Si nanocrystal, light emitting diode, nanowires

Summary:

In this work, a new technique for improving the optical and electrical properties of Si NC LEDs by employing indium tin oxide (ITO) nanowires (NWs) was investigated. The structure of Si NC LED investigated here was ITO NWs/ITO (100 nm)/n-SiC (50 nm)/Si NCs in SiNx (50 nm)/p+-Si substrate. The Si NC LED without ITO NWs was also fabricated for comparison. As the growth temperature of ITO NWs decreased, the ITO NWs were smaller and less uniform in size as compared to those synthesized at 500 °C. The ITO NWs had a tendency to grow perpendicularly above the surface, even though all of them were not perfectly oriented on the surface. I-V characteristics of Si NC LEDs with ITO NWs were improved as compared to those of Si NC LEDs without ITO NWs. This was attributed to an enhancement in the current spreading property of the ITO layer and a decrease in the dynamic resistance of the whole Si NC LED. Moreover, light output power and wall-plug efficiency of the Si NC LED with ITO NWs were also enhanced. We will discuss on the electrical and optical properties of Si NC LED with ITO NWs in detail.