Spatio-Time-Resolved Cathodoluminescence Spectroscopy Imaging: Microscopic Recombination Kinetics in Semi-Polar InGaN Quantum Wells

Enhancement of internal quantum efficiency (IQE) in InGaN quantum wells by insertion of a superlattice interlayer and applying the pulsed growth regime is investigated by a set of time-resolved optical techniques. A threefold IQE increase was achieved in the structure with the superlattice. It was ascribed to the net effect of decreased internal electrical field due to lower strain and altered carrier localization conditions. Pulsed MOCVD growth also resulted in twice higher IQE, presumably due to better control of defects in the structure. An LED (light emitting diode) structure with a top p-type contact GaN layer was manufactured by using both growth techniques with the peak IQE equal to that in the underlying quantum well structure. The linear recombination coefficient was found to gradually increase with excitation due to carrier delocalization, and the latter dependence was successfully used to fit the IQE droop.

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Phonon satellites and time-resolved studies of carrier recombination dynamics in InGaN quantum wells

Superlattices and Microstructures ◽

10.1016/j.spmi.2007.03.014 ◽

2007 ◽

Vol 41 (5-6) ◽

pp. 419-424 ◽

Cited By ~ 4

Author(s):

S.M. Olaizola ◽

W.H. Fan ◽

D.J. Mowbray ◽

M.S. Skolnick ◽

P.J. Parbrook ◽

...

Keyword(s):

Quantum Wells ◽

Time Resolved ◽

Carrier Recombination ◽

Recombination Dynamics ◽

Ingan Quantum Wells

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Localization versus carrier-screening effects in InGaN quantum wells — A time-resolved cathodoluminescence study

10.1063/1.1994110 ◽

2005 ◽

Author(s):

A. Bell

Keyword(s):

Quantum Wells ◽

Carrier Screening ◽

Time Resolved ◽

Ingan Quantum Wells ◽

Cathodoluminescence Study

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Analysis of Time-resolved Photoluminescence of InGaN Quantum Wells Using the Carrier Rate Equation

Japanese Journal of Applied Physics ◽

10.1143/jjap.49.112402 ◽

2010 ◽

Vol 49 (11) ◽

pp. 112402 ◽

Cited By ~ 17

Author(s):

Hyunsung Kim ◽

Dong-Soo Shin ◽

Han-Youl Ryu ◽

Jong-In Shim

Keyword(s):

Quantum Wells ◽

Rate Equation ◽

Carrier Rate ◽

Time Resolved ◽

Time Resolved Photoluminescence ◽

Ingan Quantum Wells

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Similarities in the Optical Properties of Hexagonal and Cubic InGaN Quantum Wells

MRS Proceedings ◽

10.1557/proc-693-i7.5.1 ◽

2001 ◽

Vol 693 ◽

Author(s):

S. F. Chichibu ◽

M. Sugiyama ◽

T. Onuma ◽

T. Kuroda ◽

A. Tackeuchi ◽

...

Keyword(s):

Optical Properties ◽

Quantum Wells ◽

Multiple Quantum Well ◽

Intrinsic Property ◽

Multiple Quantum ◽

Time Resolved ◽

Exciton Localization ◽

Peak Energy ◽

Stretched Exponential Decay ◽

Ingan Quantum Wells

AbstractOptical properties of fully-strained wurtzite and zincblende InxGa1-xN/GaN multiple quantum well (MQW) structures were compared to discuss the origin of exciton localization. In contrast to the hexagonal InGaN MQWs, the photoluminescence (PL) peak energy of cubic InGaN MQWs showed a moderate blueshift with decreasing well thickness, L, and low-temperature PL decay time of the cubic MQWs did not depend strongly on L. The results imply that the wavefunction overlap in cubic InGaN MQWs was not reduced compared to the hexagonal ones, since they do not suffer from the electric field normal to the QW plane due either to spontaneous or piezoelectric polarization. Both MQWs exhibited a large and composition-dependent bandgap bowing, and time-resolved PL (TR-PL) signals showed a stretched-exponential decay even at room temperature. The exciton localization is considered to be an intrinsic property of InGaN.

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The impact of point defects in n-type GaN layers on thermal decomposition of InGaN/GaN QWs

Scientific Reports ◽

10.1038/s41598-021-81017-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Mikolaj Grabowski ◽

Ewa Grzanka ◽

Szymon Grzanka ◽

Artur Lachowski ◽

Julita Smalc-Koziorowska ◽

...

Keyword(s):

Quantum Wells ◽

High Temperatures ◽

Point Defects ◽

X Ray Diffraction ◽

Helium Ions ◽

X Ray ◽

Sapphire Substrates ◽

Transmission Electron ◽

The Impact ◽

Ingan Quantum Wells

AbstractThe aim of this paper is to give an experimental evidence that point defects (most probably gallium vacancies) induce decomposition of InGaN quantum wells (QWs) at high temperatures. In the experiment performed, we implanted GaN:Si/sapphire substrates with helium ions in order to introduce a high density of point defects. Then, we grew InGaN QWs on such substrates at temperature of 730 °C, what caused elimination of most (but not all) of the implantation-induced point defects expanding the crystal lattice. The InGaN QWs were almost identical to those grown on unimplanted GaN substrates. In the next step of the experiment, we annealed samples grown on unimplanted and implanted GaN at temperatures of 900 °C, 920 °C and 940 °C for half an hour. The samples were examined using Photoluminescence, X-ray Diffraction and Transmission Electron Microscopy. We found out that the decomposition of InGaN QWs started at lower temperatures for the samples grown on the implanted GaN substrates what provides a strong experimental support that point defects play important role in InGaN decomposition at high temperatures.

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