Growth Behavior of High-Indium-Composition InGaN Quantum Dots Using Growth Interruption Method

Abstract

High-indium-composition InGaN quantum dots (QDs) have been grown using a growth interruption method by metal organic vapor phase epitaxy. Effects of V/III ratio and temperature on the density, size, and formation mechanism of InGaN QDs by this method are investigated by atomic force microscopy and photoluminescence measurements. At a V/III ratio of 16600 and a temperature of 650 C, adatoms can migrate on the surface and combine with each other to form QDs to relax stress when growth is interrupted. A lower V/III ratio of 8300 can increase the migration capability of adatoms, and stress is relaxed by formation of dots when the first nominal InGaN layer is grown, which results in the lower density and higher indium composition of QDs after the second InGaN layer growth. Three-dimensional growth can be enhanced and the density of QDs increases at a temperature of 600 C. #

InGaN/GaN multilayer quantum dots yellow-green light-emitting diode with optimized GaN barriers

“…In addition, micro-PL at low temperature shows a sharp peak from single QDs with the same QD growth parameters in our previous reports [16,36]. Based on the micro-PL measurements, we believe that the optical properties of our samples reflect the quantum confinement effect in the InGaN quantum dots.…”

“…To circumvent the above disadvantages, various approaches are adopted, such as InGaN quantum dots (QDs) grown as the alternative active region [13,14] and InGaN QWs grown on nonpolar or semipolar planes [6,15]. In previous reports, growth behaviors of high-In-content InGaN quantum dots using a growth interruption method are intensively investigated [16-20], which paves the way to high-efficiency QD LEDs. As the capping layer of InGaN QDs, GaN barrier is critical to the performance of multilayer InGaN QDs.…”

Red Emission of InGaN/GaN Multiple‐Quantum‐Well Light‐Emitting Diode Structures with Indium‐Rich Clusters

“…Some growth methods were proposed to suppress the indium segregation, such as using quantum dots (QDs) instead of QWs to be the active region, which is considered as a preferred solution for the green gap problem . Because of the growth mechanism of QDs, the stress relaxation during the formation of QDs will weaken the QCSE and thus improve the crystal quality . Compared with MQWs LEDs, green and red LEDs based on QDs have wavelength‐stability advantages when the injection current increases.…”

Growth mechanism of InGaN nanodots on three‐dimensional GaN structures

“…As mentioned above, the InGaN NDs are formed from the InGaN layer by the Stranski–Krastanov mode (S‐K mode), using the growth interruption method. During the growth interruption step, indium and gallium adatoms of the InGaN layer migrate toward other facets, in order to relax the strain between the InGaN/GaN interface . However, InGaN NDs were formed even without growth interruption.…”