Silicon-based light emitting diode for enhancing light extraction efficiency and method of fabricating the same

Abstract

Due to the indirect transition characteristic of silicon semiconductors, the light extraction efficiency of a silicon-based light emitting diode is lower than that of a compound semiconductor-based light emitting diode. For this reason, there are difficulties in practically using and commercializing silicon-based light emitting diodes developed so far. Provided is a silicon-based light emitting including: a substrate with a lower electrode layer on a lower surface thereof; a lower doped layer that is formed on an upper surface of the substrate and supplies carriers to an emitting layer; the emitting layer that is a silicon semiconductor layer including silicon quantum dots or nanodots formed on the lower doped layer and has a light-emitting characteristic; an upper doped layer that is formed on the emitting layer and supplies carriers to the emitting layer; an upper electrode layer formed on the upper doped layer; and a surface structure including a surface pattern formed on the upper electrode layer, a surface structure including an upper electrode pattern and an upper doped pattern formed by patterning the upper electrode layer and the upper doped layer, or a surface structure including the surface pattern, the upper electrode pattern, and upper doped pattern, wherein the surface structure enhances the light extraction efficiency of light emitted from the emitting layer according to geometric optics.