Original Publication Date
Applied Physics Letters
DOI of Original Publication
Date of Submission
We investigated the internal quantum efficiency (IQE) and the relative external quantum efficiency (EQE) of m-plane InGaN light emitting diodes(LEDs) grown on m-plane freestanding GaN emitting at ∼400 nm for current densities up to 2500 A/cm2. IQE values extracted from intensity and temperature dependent photoluminescencemeasurements were consistently higher, by some 30%, for the m-plane LEDs than for reference c-plane LEDs having the same structure, e.g., 80% versus 60% at an injected steady-state carrier concentration of 1.2×1018 cm−3. With increasing current injection up to 2500 A/cm2, the maximum EQE is nearly retained in m-plane LEDs, whereas c-plane LEDs exhibit approximately 25% droop. The negligible droop in m-plane LEDs is consistent with the reported enhanced hole carrier concentration and light holes in m-plane orientation, thereby enhanced hole transport throughout the active region, and lack of polarization induced field. A high quantum efficiency and in particular its retention at high injection levels bode well for m-plane LEDs as candidates for general lighting applications.
Li, X., Ni, X., Lee, J., et al. Efficiency retention at high current injection levels in m-plane InGaN light emitting diodes. Applied Physics Letters, 95, 121107 (2009). Copyright © 2009 AIP Publishing LLC.
Is Part Of
VCU Electrical and Computer Engineering Publications