Integrated Rib Waveguide-Photodetector Using Si/Si1−xGex Multiple Quantum Wells for Long Wavelenghts

1991 ◽  
Vol 220 ◽  
Author(s):  
V. P. Kesan ◽  
P. G. May ◽  
G. V. Treyz ◽  
E. Bassous ◽  
S. S. Iyer ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Internal Quantum Efficiency ◽  
Optical Quality ◽  
Silicon Substrates ◽  
Multiple Quantum ◽  
X Ray Diffraction ◽  
Cross Sectional ◽  
Long Wavelength ◽  
Response Bandwidth ◽  
Soi Substrates

ABSTRACTWe have investigated the structural, electrical, and optical quality of epitaxial Si and Si1−xGex films grown by MBE on SIMOX (Separation by IMplanted OXygen) silicon substrates. Epitaxial films grown on these SOI substrates have been characterized using planar and cross-sectional TEM, high resolution X-ray diffraction, SIMS, and Seeco chemical etching to delineate defects. We have fabricated Si/SiGe P-i-N photodetectors integrated with Si waveguides on SOI for long wavelength applications. Low reverse leakage current densities were seen in these device structures. The photodetector exhibited an internal quantum efficiency of 50% at 1.1 μm with a frequency response bandwidth of 2 GHz.

Structural and Optical Properties of Al0.30Ga0.70N/AlN Multiple Quantum Wells Grown on Vicinal 4H p-SiC Substrates by Molecular Beam Epitaxy

MRS Advances ◽  
2016 ◽  
Vol 2 (5) ◽  
pp. 271-276
Author(s):  
Gordie Brummer ◽  
Denis Nothern ◽  
T.D. Moustakas
Keyword(s):  
Optical Properties ◽  
Molecular Beam Epitaxy ◽  
Quantum Wells ◽  
Quantum Efficiency ◽  
Molecular Beam ◽  
Internal Quantum Efficiency ◽  
Multiple Quantum Wells ◽  
Multiple Quantum ◽  
X Ray Diffraction ◽  
Light Emitting

ABSTRACTAlGaN based multiple quantum wells (MQWs) were grown on 8° vicinal 4H p-SiC substrates by plasma-assisted molecular beam epitaxy. The MQWs were designed to emit near 300 nm using the wurtzite k.p model. The MQW periodicity and strain state were measured with X-ray diffraction. The optical properties were characterized with temperature dependent photoluminescence (PL). The internal quantum efficiency was estimated from the ratio of room temperature to 18K integrated PL intensity. Internal quantum efficiency up to 48% was achieved. These data are encouraging for future vertical and inverted ultraviolet light emitting diodes grown on p-SiC substrates.

Influence of in volatilization on photoluminescence in InGaN/GaN multiple quantum wells

2021 ◽  
Vol 11 (12) ◽  
pp. 2033-2038
Author(s):  
Kaiju Shi ◽  
Chengxin Wang ◽  
Rui Li ◽  
Shangda Qu ◽  
Zonghao Wu ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Internal Quantum Efficiency ◽  
Excitation Power ◽  
Localized States ◽  
Multiple Quantum ◽  
High Excitation ◽  
Rich Phase ◽  
Pl Spectra ◽  
Localization Effect ◽  
Effect Of Structure

Two multiple quantum well (MQW) InGaN/GaN structures emitting green light, without (A) and with (B) an indium (In) volatilization suppression technique (IVST) during growth of the active region, were fabricated. The dependencies of the photoluminescence (PL) spectra upon temperature at different levels of excitation power were investigated. The results indicate that an IVST can increase the In content while suppressing the phase separation caused by volatilization of that In incorporated in the well layers. Also, compared with Structure B with IVST, which contains one phase structure, Structure A without IVST, which contains two separate phases (i.e., an In-rich phase and an In-poor phase), exhibits higher internal quantum efficiency (IQE) at low excitation power and lower IQE at high excitation power. The former is mainly attributed to the stronger In-rich phase-related localization effect of Structure A, because the In-rich phase-related emission dominates the PL spectra of Structure A at a low excitation power; the latter is mainly due to the In-poor phase-related weaker localization effect of Structure A, because the In-poor phase-related emission dominates the PL spectra of Structure A at high excitation power because localized states in this In-rich phase are saturated.

Epitaxial Growth and Characterization of Nonpolar A-Plane AlGaN-Based Multiple Quantum Wells

2018 ◽  
Vol 934 ◽  
pp. 8-12
Author(s):  
Jian Guo Zhao ◽  
Xiong Zhang ◽  
Jia Qi He ◽  
Shuai Chen ◽  
Zi Li Wu ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Chemical Vapor ◽  
Multiple Quantum Wells ◽  
Modulation Method ◽  
Duty Ratio ◽  
Organic Chemical ◽  
Multiple Quantum ◽  
X Ray Diffraction ◽  
Metal Organic

A serious of non-polar a-plane AlGaN-based multiple quantum wells (MQWs) were successfully grown on the semi-polar r-plane sapphire substrate with metal organic chemical vapor deposition technology. Intense MQWs-related emission peaks at an emission wavelength covered from 277-294 nm were observed based on the photoluminescence measurement. It was found that the employment of the trimethyl-aluminum (TMAl) flow duty-ratio modulation method which was developed based on the two-way pulsed-flows growth technique played a crucial role to control the Al composition of the non-polar a-plane AlGaN epi-layers. The non-polar a-plane AlGaN-based MQWs were deposited with the new developed TMAl flow duty-ratio modulation technique. Evident-3th order X-ray diffraction (XRD) satellite peak was observed from the high resolution-XRD measurement, proving the successful growth of non-polar a-plane AlGaN-based MQWs with abrupt hetero-interfaces.

Temperature Dependence of Photoresponse in p-Type GaAs/AlGaAs Multiple Quantum Wells: Theory and Experiment

1999 ◽  
Vol 607 ◽  
Author(s):  
F. Szmulowicz ◽  
A. Shen ◽  
H. C. Liu ◽  
G. J. Brown ◽  
Z. R. Wasilewski ◽  
...  
Keyword(s):  
Quantum Wells ◽  
Temperature Dependence ◽  
Bound States ◽  
Light Hole ◽  
Multiple Quantum ◽  
Temperature Dependent ◽  
Long Wavelength ◽  
Hole Level ◽  
Polarization Characteristics ◽  
P Type

AbstractThis paper describes a study of the photoresponse of long-wavelength (LWIR) and mid-infrared (MWIR) p-type GaAs/AlGaAs quantum well infrared photodetectors (QWIPs) as a function of temperature and QWIP parameters. Using an 8x8 envelope-function model (EFA), we designed and calculated the optical absorption of several bound-to-continuum (BC) structures, with the optimum designs corresponding to the second light hole level (LH2) coincident with the top of the well. For the temperature-dependent study, one non-optimized LWIR and one optimized MWIR samples were grown by MBE and their photoresponse and absorption characteristics measured to test the theory. The theory shows that the placement of the LH2 resonance at the top of the well for the optimized sample and the presence of light-hole-like quasi-bound states within the heavy-hole continuum for the nonoptimized sample account for their markedly different thermal and polarization characteristics. In particular, the theory predicts that, for the LWIR sample, the LH-like quasi-bound states should lead to an increased Ppolarized photoresponse as a function of temperature. Our temperature dependent photoresponse measurements corroborate most of the theoretical findings with respect to the long-wavelength threshold, shape, and polarization and temperature dependence of the spectra.

V-Defect and Dislocation Analysis in InGaN Multiple Quantum Wells on Patterned Sapphire Substrate

2018 ◽  
Vol 787 ◽  
pp. 37-41
Author(s):  
Huan You Wang ◽  
Qiao Lai Tan ◽  
Gui Jin
Keyword(s):  
Quantum Wells ◽  
Strain Relaxation ◽  
Chemical Vapor ◽  
Multiple Quantum ◽  
Cross Sectional ◽  
Patterned Sapphire Substrate ◽  
Sapphire Substrates ◽  
Transmission Electron ◽  
Multi Quantum Well ◽  
Patterned Sapphire Substrates

InGaN/GaN multiquantum well (MQW) structures have been grown on cone-shaped patterned sapphire substrates (CPSS) by metalorganic chemical vapor deposition (MOCVD). From the transmission electron microscopy (TEM) results, we found that most of the threading dislocations (TDs) in the trench region of the CPSS were bent by lateral growth mode. Also the staircase-like TDs were observed near the slant region of the cone pattern, they converged at the slope of the cone patterned region by staircase-upward propagation, which seems to effectively prevent TDs from vertical propagation in the trench region. The associated dislocation runs up into the overgrown GaN layer and MQW, and some (a+c) dislocations were shown to decompose inside the multi-quantum well, giving rise to a misfit segment in the c-plane and a V-shape defect. From cross-sectional TEM, we found that all V defects are not always connected with TDs at their bottom, some V defects are generated from the stacking mismatch boundaries induced by stacking faults which are formed within the MQW due to the strain relaxation.

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