Metalorganic chemical vapor deposition of quaternary AlInGaN multiple quantum well structures for deep ultraviolet emitters

Abstract

AbstractWe report on the growth of quaternary AlInGaN layers and MQWs by two different metalorganic chemical vapor deposition (MOCVD) techniques such as pulsed atomic layer epitaxy (PALE) and pulsed MOCVD (PMOCVD). For both growth processes, emission wavelength of quaternary MQWs can be tuned from 350 nm to 300 nm by simply changing the unit growth cell configurations. The PALE grown AlInGaN MQWs have a very smooth surface, few band tail states and exhibit a band-to-band emission. The PMOCVD grown AlInGaN MQWs exhibit a high density of band tail states, which strongly enhance spontaneous emission. Based on the characterization by photoluminescence, X-ray diffraction and AFM, both MOCVD techniques grown quaternary samples are shown to be promising for fabricating the active region of deep UV LEDs.