Strain recovery in partially relaxed In0.2Ga0.8As/GaAs single quantum wells with increasing GaAs cap layer thickness

Abstract Three InGaN/GaN MQWs samples with varying GaN cap layer thickness were grown by metalorganic chemical vapor deposition (MOCVD) to investigate the optical properties. We found that a thicker cap layer is more effective in preventing the evaporation of the In composition in the InGaN quantum well layer. Furthermore, the quantum-confined Stark effect (QCSE) is enhanced with increasing the thickness of GaN cap layer. In addition, compared with the electroluminescence measurement results, we focus on the difference of localization states and defects in three samples induced by various cap thickness to explain the anomalies in room temperature photoluminescence measurements. We found that too thin GaN cap layer will exacerbates the inhomogeneity of localization states in InGaN QW layer, and too thick GaN cap layer will generate more defects in GaN cap layer.

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Optical and structural characteristics of high indium content InGaN/GaN multi-quantum wells with varying GaN cap layer thickness

Journal of Applied Physics ◽

10.1063/1.4907670 ◽

2015 ◽

Vol 117 (5) ◽

pp. 055709 ◽

Cited By ~ 14

Author(s):

J. Yang ◽

D. G. Zhao ◽

D. S. Jiang ◽

P. Chen ◽

J. J. Zhu ◽

...

Keyword(s):

Quantum Wells ◽

Layer Thickness ◽

Structural Characteristics ◽

Indium Content ◽

Cap Layer ◽

High Indium Content

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Temperature‐dependent critical layer thickness for In0.36Ga0.64As/GaAs single quantum wells

Applied Physics Letters ◽

10.1063/1.104511 ◽

1991 ◽

Vol 58 (8) ◽

pp. 854-855 ◽

Cited By ~ 57

Author(s):

M. J. Ekenstedt ◽

S. M. Wang ◽

T. G. Andersson

Keyword(s):

Quantum Wells ◽

Layer Thickness ◽

Critical Layer ◽

Single Quantum ◽

Temperature Dependent ◽

Critical Layer Thickness

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Influence of the cap layer thickness on the optical properties of near surface GaInAs/GaAs quantum wells

European Materials Research Society Symposia Proceedings - Semiconductor Materials for Optoelectronics and LTMBE Materials, PROCEEDINGS OF SYMPOSIUM A ON SEMICONDUCTOR MATERIALS FOR OPTOELECTRONIC DEVICES, OEICS AND PHOTONICS AND SYMPOSIUM B ON LOW TEMPERATURE MOLECULAR BEAM EPITAXIAL III–V MATERIALS: PHYSICS AND APPLICATIONS OF THE 1993 E-MRS SPRING CONFERENCE ◽

10.1016/b978-0-444-81769-3.50023-1 ◽

1993 ◽

pp. 198-200

Author(s):

J. Dreybrodt ◽

F. Faller ◽

A. Forchel ◽

J.P. Reithmaier

Keyword(s):

Optical Properties ◽

Quantum Wells ◽

Layer Thickness ◽

Near Surface ◽

Cap Layer

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The dependence of the carrier density and the mobility on the spacer-layer thickness in modulation-doped AlxGa1−xAs/InyGa1−yAs/GaAs asymmetric single quantum wells

Applied Surface Science ◽

10.1016/s0169-4332(01)00122-2 ◽

2001 ◽

Vol 177 (1-2) ◽

pp. 1-7 ◽

Cited By ~ 8

Author(s):

M Jung ◽

T.W Kim ◽

D.U Lee ◽

D.C Choo ◽

K.H Yoo ◽

...

Keyword(s):

Quantum Wells ◽

Layer Thickness ◽

Carrier Density ◽

Single Quantum ◽

Spacer Layer Thickness ◽

Spacer Layer

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Photoluminescence Investigations of High Purity Mbe-Grown Sil−xGex/Si Single Quantum Wells

MRS Proceedings ◽

10.1557/proc-298-85 ◽

1993 ◽

Vol 298 ◽

Cited By ~ 1

Author(s):

M. Wachter ◽

F. Schdffler ◽

K. Thonke ◽

R. Sauer ◽

H.-J. Herzog ◽

...

Keyword(s):

Quantum Wells ◽

Strain Energy ◽

Free Exciton ◽

Sige Layer ◽

Band Edge ◽

Background Concentration ◽

Single Quantum ◽

Single Quantum Well ◽

Cap Layer ◽

Shallow Impurities

AbstractSil-xGex/Si(100) single quantum well samples were grown by MBE with x varying from 18.5% to 36%, well widths Lz from 1.1 nm to 175 nm, and growth temperatures To in the range from 350°C to 750°C. We studied the photoluminescence (PL) properties in detail using Fourier transform spectroscopy. In most of the samples, the dominant and phononresolved SiGe band edge PL exhibits exclusively free exciton luminescence even at sample temperatures as low as 2 K. From the absence of bound excitons we conclude that the background concentration of shallow impurities is low in our SiGe layers. Variation of the growth temperature of the Si cap layer strongly influences the efficiency of the SiGe band edge PL at higher temperatures, whereas the PL efficiency is less affected at T=4 K. This indicates a reduction of the concentration of non-radiative defects in the cap layer when it is grown at higher temperatures. A broad PL band 150 meV below the SiGe bandgap, supposed to be typical for MBE-grown material, is weakly observed in only a few samples. The strength of the broad PL band does not unambiguously depend on the strain energy density in the SiGe layer as recently suggested.

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