Lin LU, Yi LANG, Fu-jun XU, et al. Performance Enhancement of AlGaN-based Deep-ultraviolet Light Emitting Diodes by Employing Irregular H-shaped Quantum Barriers. [J]. Chinese Journal of Luminescence 41(6):714-718(2020)
Lin LU, Yi LANG, Fu-jun XU, et al. Performance Enhancement of AlGaN-based Deep-ultraviolet Light Emitting Diodes by Employing Irregular H-shaped Quantum Barriers. [J]. Chinese Journal of Luminescence 41(6):714-718(2020) DOI： 10.3788/fgxb20204106.0714.
Performance Enhancement of AlGaN-based Deep-ultraviolet Light Emitting Diodes by Employing Irregular H-shaped Quantum Barriers
AlGaN-based deep ultraviolet light-emitting diodes (DUV-LEDs) employing irregular H-shaped quantum barriers in the active region by modulating Al composition have been investigated. It has been found that the H-shaped quantum barriers by insertion of double spike barriers with higher Al composition can effectively improve both the internal quantum efficiency (IQE) and light output power (LOP) compared to commonly adopted single-Al-composition barrier for AlGaN multiple quantum wells (MQWs). It is verified that electrons in the active region are effectively blocked by the raised barriers, while holes can gain more kinetic energy to cross the barrier height and then be injected into the active region. Thus the carrier recombination rate in the DUV-LEDs adopting the H-shaped quantum barriers can prevail much over the conventional one.
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