Fabrication of suspended light-emitting diode and waveguide on a single chip

Abstract

We attempt to integrate light-emitting diode (LED) and waveguide on the same GaN-on-silicon platform, which is fashioned with suspended p–n junction InGaN/GaN multiple quantum wells. Silicon substrate is removed to form highly confined waveguide structures and suspended LED. The light emission measurements experimentally demonstrate that part of the LED emission is coupled into suspended waveguide. The light is then guided in the waveguide and propagates along the waveguide structure, and is finally diffracted into the air at the waveguide output facet. The light spectra captured by a micro-transmittance setup confirm that the lateral light propagation inside the waveguide is electrically driven and power-dependent. These results indicate that the proposed integrated device is promising for the monolithic integration of LED with waveguide and photodetector toward next-generation photonic chips based on the GaN-on-silicon platform.