GaN-based resonant-cavity light-emitting diode towards a vertical-cavity surface-emitting laser

The letter reports the successful fabrication of GaN-based resonant cavity light-emitting diodes (RCLEDs) with nanoporous (NP) GaN/n-GaN distributed Bragg reflector (DBR). To realize the designed central wavelength and high reflectivity, the precise thickness control of NP GaN layer is extremely critical. By introducing the concept of space charge region in the thickness design of the n
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-GaN epitaxial growth for nanoporous GaN, accurate regulation of the centre wavelength of the NP GaN DBR reflection spectrum was achieved. Under light injection condition, longitudinal mode laser was observed at 438 nm, with a full width at half maximum (FWHM) of approximately 0.7 nm. Under electrical injection condition, the FWHM of the RCLED emission peak was about 3.4 nm.