Stable-wavelength operation of europium-doped GaN nanocolumn light-emitting diodes grown by rf-plasma-assisted molecular beam epitaxy
For the first time, a rare-earth-doped GaN nanocolumn light-emitting diode is fabricated on an n-type (111) Si substrate, grown by rf-plasma-assisted molecular beam epitaxy. The nanocolumn structure remained in the n-GaN and europium-doped GaN active regions, but the lateral growth was enhanced in the p-GaN region such that a continuous film was obtained. Clear diode characteristics and a sharp red luminescence with two dominant peaks at 620.3 and 633.8 nm were observed at room temperature. The shift in the wavelength with an increase in the injected current was <0.2 nm. Thus, this device has the potential for application as a stable-wavelength optical device.
