Thin-film vertical monolithic III-nitride optoelectronic system

III-nitride multi-quantum well (MQW) diodes are multifunctional devices and exhibit intriguing spectral overlap between emission and responsivity spectra. By reducing device thickness, thin-film vertical (TFV) MQW diodes not only inhibit confined optical waveguide modes but also achieve mode-matching light emission or detection naturally. Here, we monolithically integrated TFV MQW diodes on a III-nitride-on-silicon platform that separately serve as a light-emitting diode and a photodiode. The experimental results confirm that TFV devices reduce the number of confined waveguide modes and eliminate transverse light crosstalk, which leads to a significant reduction in the background photocurrent level at 10−9 A. The monolithic III-nitride optoelectronic systems demonstrate the great potential for full-duplex visible light communication and proximity sensing.