Optical Properties of AlGaN Quantum Well Structures

1999 ◽  
Vol 595 ◽  
Author(s):  
Hideki Hirayama ◽  
Yasushi Enomoto ◽  
Atsuhiro Kinoshita ◽  
Akira Hirata ◽  
Yoshinobu Aoyagi
Keyword(s):  
Optical Properties ◽  
Quantum Well ◽  
Quantum Wells ◽  
Vapor Phase ◽  
Wide Bandgap ◽  
Near Band Edge ◽  
Quantum Well Structures ◽  
Al Content ◽  
Pl Emission ◽  
High Al Content

AbstractWe demonstrate 230-250 nm efficient ultraviolet (UV) photoluminescence (PL) from AlN(AlGaN)/AlGaN multi-quantum-wells (MQWs) fabricated by metalorganic vapor-phase-epitaxy (MOVPE). Firstly, we show the PL properties of high Al content AlGaN bulk (Al content: 85-95%) emitting from near band-edge. We systematically investigated the PL properties of AlGaN-MQWs consisting of wide bandgap AlGaN (Al content: 53-100%) barrier. We obtained efficient PL emission of 234 and 245 nm from AlN/Al0.18Ga0.82N and Al0.8Ga0.2N/Al0.18Ga0.82N MQWs, respectively, at 77 K. The optimum value of well thickness was approximately 1.5 nm. The emission from the AlGaN MQWs were several tens of times stronger than that of bulk AlGaN. We found that the most efficient PL is obtained at around 240 nm from AlGaN MQWs with Al0.8Ga0.2N barriers. Also, we found that the PL from AlGaN MQW is as efficient as that of InGaN QWs at 77 K.

scholarly journals Optical Properties of AlGaN Quantum Well Structures

2000 ◽  
Vol 5 (S1) ◽  
pp. 696-702 ◽  
Author(s):  
Hideki Hirayama ◽  
Yasushi Enomoto ◽  
Atsuhiro Kinoshita ◽  
Akira Hirata ◽  
Yoshinobu Aoyagi
Keyword(s):  
Optical Properties ◽  
Quantum Wells ◽  
Wide Bandgap ◽  
Near Band Edge ◽  
Quantum Well Structures ◽  
Al Content ◽  
Organic Vapor ◽  
Metal Organic ◽  
Pl Emission ◽  
High Al Content

We demonstrate 230-250 nm efficient ultraviolet (UV) photoluminescence (PL) from AlN(AlGaN)/AlGaN multi-quantum-wells (MQWs) fabricated by metal-organic vapor-phase-epitaxy (MOVPE). Firstly, we show the PL properties of high Al content AlGaN bulk (Al content: 85-95%) emitting from near band-edge. We systematically investigated the PL properties of AlGaN-MQWs consisting of wide bandgap AlGaN (Al content: 53-100%) barrier. We obtained efficient PL emission of 234 and 245 nm from AlN/Al0.18Ga0.82N and Al0.8Ga0.2N/Al0.18Ga0.82N MQWs, respectively, at 77 K. The optimum value of well thickness was approximately 1.5 nm. The emission from the AlGaN MQWs were several tens of times stronger than that of bulk AlGaN. We found that the most efficient PL is obtained at around 240 nm from AlGaN MQWs with Al0.8Ga0.2N barriers. Also, we found that the PL from AlGaN MQW is as efficient as that of InGaN QWs at 77 K.

Influence of Al content in the barrier on the optical properties of GaAs/AlxGa1−xAs (x=0.1–1) multiple-quantum-well structures

1992 ◽  
Vol 46 (11) ◽  
pp. 6947-6954 ◽  
Author(s):  
Nguyen Hong Ky ◽  
J. D. Ganière ◽  
M. Gailhanou ◽  
F. Morier-Genoud ◽  
D. Martin ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Well ◽  
Multiple Quantum Well ◽  
Multiple Quantum ◽  
Quantum Well Structures ◽  
Al Content

scholarly journals Role of Strain-Induced Microscale Compositional Pulling on Optical Properties of High Al Content AlGaN Quantum Wells for Deep-Ultraviolet LED

2022 ◽  
Vol 17 (1) ◽  
Author(s):  
Shiqiang Lu ◽  
Zongyan Luo ◽  
Jinchai Li ◽  
Wei Lin ◽  
Hangyang Chen ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Wells ◽  
Tensile Strain ◽  
Light Emitting Diode ◽  
Formation Enthalpy ◽  
Local Variation ◽  
Multiple Quantum ◽  
Al Content ◽  
Deep Ultraviolet ◽  
High Al Content

AbstractA systematic study was carried out for strain-induced microscale compositional pulling effect on the structural and optical properties of high Al content AlGaN multiple quantum wells (MQWs). Investigations reveal that a large tensile strain is introduced during the epitaxial growth of AlGaN MQWs, due to the grain boundary formation, coalescence and growth. The presence of this tensile strain results in the microscale inhomogeneous compositional pulling and Ga segregation, which is further confirmed by the lower formation enthalpy of Ga atom than Al atom on AlGaN slab using first principle simulations. The strain-induced microscale compositional pulling leads to an asymmetrical feature of emission spectra and local variation in emission energy of AlGaN MQWs. Because of a stronger three-dimensional carrier localization, the area of Ga segregation shows a higher emission efficiency compared with the intrinsic area of MQWs, which is benefit for fabricating efficient AlGaN-based deep-ultraviolet light-emitting diode.

-ORIENTED GaAs/AlGaAs AND InGaAs/GaAs QUANTUM WELL STRUCTURES FABRICATED BY MOVPE AND THEIR OPTICAL AND STRAIN-INDUCED PIEZOELECTRIC PROPERTIES

2000 ◽  
Vol 10 (01) ◽  
pp. 93-101
Author(s):  
SOOHAENG CHO ◽  
A. SANZ-HERVÁS ◽  
JONGSEOK KIM ◽  
A. MAJERFELD ◽  
B. W. KIM
Keyword(s):  
Quantum Well ◽  
Electric Fields ◽  
Vapor Phase ◽  
Atmospheric Pressure ◽  
Piezoelectric Properties ◽  
Single Quantum ◽  
Single Quantum Well ◽  
Quantum Well Structures ◽  
Gaas Substrates ◽  
Pl Emission

We report our recent results on the growth and properties of GaAs/AlGaAs and strained InGaAs/GaAs quantum well (QW) structures grown on (111)A GaAs substrates by atmospheric-pressure metalorganic vapor phase epitaxy. We have fabricated 25-period GaAs/AlGaAs multiquantum well structures with good crystal quality, high photoluminescence (PL) emission intensity and monolayer (ML) well width fluctuation. We also present the optical and piezoelectric properties of strained InGaAs/GaAs single quantum well structures grown on (111)A GaAs. Photoreflectance spectroscopy has been performed to analyze not only the excitonic transitions, but also the Franz-Keldysh oscillations to obtain the electric fields in the well and barriers, which are necessary to determine the actual QW potential profile and, thereby, to properly interpret the properties of the structures. A PL linewidth of 9.7 meV has been also achieved, which corresponds to a 1 ML interfacial roughness for an In0.14Ga0.86As well with a 40 Å width.

Optical Properties of MBE Grown Cubic AlGaN Epilayers and AlGaN/GaN Quantum Well Structures

2000 ◽  
Vol 639 ◽  
Author(s):  
D.J. As ◽  
T. Frey ◽  
M. Bartels ◽  
A. Khartchenko ◽  
D. Schikora ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Well ◽  
Linear Increase ◽  
X Ray Diffraction ◽  
Quantum Well Structures ◽  
X Ray ◽  
Al Content ◽  
Frequency Plasma ◽  
Multi Quantum Well

ABSTRACTCubic AlyGa1−yN/GaN heterostructures on GaAs(001) substrates were grown by radio-frequency plasma-assisted molecular beam epitaxy. High resolution X-ray diffraction, spectroscopic ellipsometry and cathodoluminescence were used to characterize the structural and optical properties of the alloy epilayers. X-ray diffraction reciprocal space maps demonstrate the good crystal quality of the cubic AlyGa1−yN films. Both SE as well as room temperature CL of the AlyGa1−yN epilayer show a linear increase of the band gap with increasing Al-content. A pseudomorphically strained cubic 10 × (2.4 nm GaN/ 4.8 nm Al0.12Ga0.88N) multi-quantum well (MQW) structure has been realized. Cathodoluminescence clearly demonstrates strong radiative recombination due to quantized states in the GaN well layer at a photon energy of 3.323 eV.

OMVPE Growth of GalnAs/InP Quantum Well Structures

1987 ◽  
Vol 102 ◽  
Author(s):  
G. B. Stringfellow
Keyword(s):  
Binding Energy ◽  
Quantum Well ◽  
Quantum Wells ◽  
Vapor Phase ◽  
Atmospheric Pressure ◽  
Growth Conditions ◽  
Binding Energies ◽  
Optimum Conditions ◽  
Quantum Well Structures ◽  
Maximum Value

ABSTRACTInP/GalnAs/InP quantum well structures have been grown using atmospheric pressure organometallic vapor phase epitaxy (AP-OMVPE). The optimum conditions for growth of extremely abrupt interfaces were studied. The optimum orientation was exactly (100). The growth had to be interrupted for 40 seconds at the first interface and 2 minutes at the 2nd interface to obtain the most abrupt interfaces. The narrowest photoluminescence half widths were obtained at the lowest values (31) of V/III ratio in the input vapor phase. These growth conditions allow the growth of wells as thin as <10Å with photoluminescence (PL) spectra consisting of doublets or triplets. The extremely narrow peaks correspond to regions of the quantum well differing in thickness by a single monolayer. The energy separations of the neighboring peaks are found to increase with decreasing well width until, at a thickness of approximately 12 Å, the separation begins to decrease rapidly with decreasing well width. The exciton binding energies in the quantum wells have also been measured using thermally modulated PL. The binding energy is found to increase with decreasing well width until a maximum value of approximately 17 meV is measured for a nominal well width of approximately 13 Å. For thinner wells the exciton binding energy is found to decrease with decreasing well width.

Electronic and Optical Properties of Bulk GaN and GaN/AlGaN Quantum Well Structures

1997 ◽  
Vol 468 ◽  
Author(s):  
M. Suzuki ◽  
T. Uenoyama
Keyword(s):  
Optical Properties ◽  
Quantum Well ◽  
Quantum Wells ◽  
Electronic Structures ◽  
Carrier Density ◽  
Uniaxial Strain ◽  
Crystal Symmetry ◽  
Quantum Well Structures ◽  
Electronic And Optical Properties ◽  
Bulk Gan

ABSTRACTElectronic structures and optical gains of bulk GaN and GaN/AlGaN quantum wells (QWs) are theoretically investigated for the wurtzite and the zincblende structures, using the k-p theory. It is found that the lower crystal symmetry, that is the wurtzite, is preferable for the lower threshold carrier density in the bulk. Although the QW structure leads to symmetry lowering only in the zincblende, we can not find a significant benefit of the zincblende QWs. As for the reduction of the threshold carrier density, biaxial strains are more effective in the zincblende. However, the threshold carrier density is still higher than in the wurtzite. It is proposed that the uniaxial strain in the c-plane of the wurtzite is more useful for reducing it.

LINEAR AND NONLINEAR INTERSUBBAND OPTICAL ABSORPTION OF FINITE AND INFINITE SEMI-PARABOLIC QUANTUM WELLS

2011 ◽  
Vol 25 (07) ◽  
pp. 497-507 ◽  
Author(s):  
M. J. KARIMI ◽  
A. KESHAVARZ ◽  
A. POOSTFORUSH
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Optical Absorption ◽  
Quantum Well ◽  
Quantum Wells ◽  
Resonant Peak ◽  
Energy Eigenvalues ◽  
Finite Case ◽  
Infinite Case ◽  
Index Changes

In this work, the optical absorption coefficients and the refractive index changes for the infinite and finite semi-parabolic quantum well are calculated. Numerical calculations are performed for typical GaAs / Al x Ga 1-x As semi-parabolic quantum well. The energy eigenvalues and eigenfunctions of these systems are calculated numerically. Optical properties are obtained using the compact density matrix approach. Results show that the energy eigenvalues and the matrix elements of the infinite and finite cases are different. The calculations reveal that the resonant peaks of the optical properties of the finite case occur at lower values of the incident photon energy with respect to the infinite case. Results indicate that the maximum value of the refractive index changes for the finite case are greater than that of the infinite case. Our calculations also show that in contrast to the infinite case, the resonant peak value of the total absorption coefficient in the case of the finite well is a non-monotonic function of the semi-parabolic confinement frequency.

Optical properties of GaBiAs single quantum well structures grown by MBE

2015 ◽  
Vol 30 (9) ◽  
pp. 094016 ◽  
Author(s):  
O Donmez ◽  
A Erol ◽  
M C Arikan ◽  
H Makhloufi ◽  
A Arnoult ◽  
...  
Keyword(s):  
Optical Properties ◽  
Quantum Well ◽  
Single Quantum ◽  
Single Quantum Well ◽  
Quantum Well Structures
Sign in / Sign up

Export Citation Format

Share Document