A new type of white light-emitting diode light source basing on fluorescent SiC

Most of the commercial white light-emitting diode (LED) light sources are made from phosphor coated blue-emitting gallium nitride (GaN) chips. This type white LED light source always has tradeoff between luminous efficacy and color rendering index (CRI). Furthermore, yellow-emitting phosphor decays much faster than the semiconductor chip, so the white color will turn into bluish over the time.

This paper will propose a new type white LED light source: using fluorescent silicon carbide (SiC) to take the place of phosphor. This new type LED has the following advantages: a) SiC is a wide bandgap semiconductor material , so it is stable; b) Fluorescent SiC has very wide emission spectrum, and it could generate white light with very high CRI; c) It is a better substrate than sapphire for the GaN growth in terms of lattice match and thermal conductivity.

This paper will cover: the growth of fluorescent SiC, its optical characterization, nanostructuring of the SiC surface for extraction efficiency enhancement, and surface passivation for further efficiency enhancement.