High-efficiency InGaN/AlInGaN multiple quantum wells with lattice-matched AlInGaN superlattices barrier

Abstract

A new approach to fabricating high-quality AlInGaN film as a lattice-matched barrier layer in multiple quantum wells (MQWs) is presented. The high-quality AlInGaN film is realized by growing the AlGaN/InGaN short period superlattices through metalorganic chemical vapor deposition, and then being used as a barrier in the MQWs. The crystalline quality of the MQWs with the lattice-matched AlInGaN barrier and that of the conventional InGaN/GaN MQWs are characterized by x-ray diffraction and scanning electron microscopy. The photoluminescence (PL) properties of the InGaN/AlInGaN MQWs are investigated by varying the excitation power density and temperature through comparing with those of the InGaN/GaN MQWs. The integral PL intensity of InGaN/AlInGaN MQWs is over 3 times higher than that of InGaN/GaN MQWs at room temperature under the highest excitation power. Temperature-dependent PL further demonstrates that the internal quantum efficiency of InGaN/AlInGaN MQWs (76.1%) is much higher than that of InGaN/GaN MQWs (21%). The improved luminescence performance of InGaN/AlInGaN MQWs can be attributed to the distinct reduction of the barrier-well lattice mismatch and the strain-induced non-radiative recombination centers.

First-principle investigation of monoclinic (Al x In y Ga1−x−y )2O3 quaternary alloys

“…The other results are first reported through this study. The effect of Aluminum and Indium addition on the lattices of β-Ga 2 O 3 alloys are primarily attributed to the atomic size difference in the material, which is also consistent with observations shown in III-Nitride-based quaternary materials [7,[35][36][37][38]. Specifically, aluminum atom is smaller than Gallium atom while Indium atom is larger than Gallium atom.…”

“…β-(Al x In y Ga 1−x−y ) 2 O 3 alloys) is non-existent in literature by far. It is important to point out that quaternary alloy layer has been implanted in well-established III-Nitride and III-V materials class to achieve desirable device performance [4,6,[31][32][33][34][35][36][37][38][39][40][41][42][43]. Quaternary alloys typically allow large tuning range of structural, electronic and optical properties that are different from the host material.…”