Effect of AlInGaN barrier layers with various TMGa flows on optoelectronic characteristics of near UV light-emitting diodes grown by atmospheric pressure metalorganic vapor phase epitaxy

Near ultraviolet light-emitting diodes (LEDs) with quaternary AlInGaN quantum barriers (QBs) are grown by atmospheric pressure metalorganic vapor phase epitaxy. The indium mole fraction of AlInGaN QB could be enhanced as we increased the TMG flow rate. Both the wavelength shift in EL spectra and forward voltage at 20 mA current injection were reduced by using AlInGaN QB. Under 100 mA current injection, the LED output power with Al0.089In0.035Ga0.876N QB can be enhanced by 15.9%, compared to LED with GaN QB. It should be attributed to a reduction of lattice mismatch induced polarization mismatch in the active layer.

► Near ultraviolet light-emitting diodes with quaternary AlInGaN quantum barriers (QB).
► The indium mole fraction of AlInGaN QB could be enhanced as we increased the TMG flow rate.
► Under 300 mA current injection, the LED output power with Al0.089In0.035Ga0.876N QB can be enhanced by 15.9%.
► A reduction of lattice mismatch induced polarization mismatch in the active layer by using AlInGaN QB.