Greatly improved efficiency droop for InGaN-based green light emitting diodes by quaternary content superlattice electron blocking layer

Abstract

We presented a low efficiency droop behavior green light emitting diodes (LEDs) with a quaternary content InAlGaN/GaN superlattice electron blocking layer (SL-EBL). The light output power shows a 57% enhancement and only 30% efficiency droop, which is attributed to a smooth band bending with a uniform carrier distribution. Index Terms-Green LEDs, Efficiency droop, Quaternary superlattice electron blocking layer

Review—A Survey of Simulations on Device Engineering of GaN-Based Light-Emitting Diodes

“…15 To resolve the aforementioned problems, numerous strategies have been published such as compositional grading of QWs for the reduction of piezoelectric field, compositional grading of quantum barriers (QBs) for the improvement of carrier transport, and grading electron blocking layer (EBL) for enhanced hole injection. [16][17][18] Quaternary (AlInGaN) and ternary (AlInN/GaN) EBLs have also been reported for better confinement of carriers within the active region. 19,20 Similarly, linearly graded (in the growth direction) AlGaN EBL has also been reported for efficient enhancement in comparison to conventional AlGaN EBL (with a fixed composition of Al: 20%).…”