Thermal Stability Of SiGe/Si Quantum Well Structures Grown By APCVD

1998 ◽  
Vol 533 ◽  
Author(s):  
Q. X. Zhao ◽  
O. Nur ◽  
U. Södervall ◽  
C. J. Patel ◽  
M. Willandera ◽  
...  
Keyword(s):  
Quantum Well ◽  
Atmospheric Pressure ◽  
Annealing Temperature ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Quantum Well Structures ◽  
Pressure Chemical ◽  
Different Temperatures ◽  
Secondary Ion ◽  
Thermal Stability Of

AbstractSingle and double Si1-xGexx/Si quantum well (QW) structures, which were grown by atmospheric pressure chemical vapor deposition (APCVD), are characterized by photoluminescence and secondary ion mass spectrometry. Systematic post-growth annealing treatments were carried out at temperatures between 600°C and 1100°C in pure N2 ambient. The interdiffusion between the Si layer and the Si1-xGex, well layers occurs at the annealing temperature around 900°C. The diffusion coefficient is deduced at different temperatures from SIMS measurements for single QW structures. The activation energy is about 3.9 eV in the temperature range between 950°C and 1100°C. The double QW structures show a similar value, but the accurate value is more difficult to obtain because it is more complicated to analyze the SIMS profile of the double QW structures. The intensity of the exciton recombination related to carriers confined in the double QW structures decreases with increasing annealing temperatures and becomes strongly suppressed at 750°C. When the annealing temperature is increased further, the intensity of the QW emission recovers. The results indicate that nonradiative centers were generated at annealing temperature of about 750°C

Growth of SiGe/Si quantum well structures by atmospheric pressure chemical vapor deposition

1993 ◽  
Vol 22 (3) ◽  
pp. 303-308 ◽  
Author(s):  
D. A. Grützmacher ◽  
T. O. Sedgwick ◽  
A. Zaslavsky ◽  
A. R. Powell ◽  
R. A. Kiehl ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Quantum Well ◽  
Vapor Deposition ◽  
Atmospheric Pressure ◽  
Chemical Vapor ◽  
Quantum Well Structures ◽  
Pressure Chemical

1.95 μm Compressively Strained Ingaas/Ingaasp Quantum Well DFB Laser With Low Threshold

1997 ◽  
Vol 484 ◽  
Author(s):  
Jie Dong ◽  
Akinoi Ubukata ◽  
Koh Matsumoto
Keyword(s):  
Quantum Well ◽  
Quantum Wells ◽  
Chemical Vapor ◽  
Double Quantum ◽  
Maximum Output ◽  
Quantum Well Structures ◽  
Double Quantum Well ◽  
Different Temperatures ◽  
Dfb Laser ◽  
Strained Quantum Well

AbstractIn this study, we demonstrate the growth of highly compressively strained InGaAs/JnGaAsP quantum well structures with large well thiclmess by low pressure metalorganic chemical vapor deposition for extending the emission wavelength of lasers. By comparing the photolumineswnce characteristics of quantum wells grown at different temperatures, it is clarified that a relatively high quality quantum well layer emittig at 2.0 μ, can be obtained at a growth temperature of 650°C. 1.95-μm-wavelength InGaAs/InGaAsP highly compressively strained quantum well DFB laser for laser spectroscopy monitors was also fabricated. Double quantum-well DFB laser operating at 1.95 μm exhibits threshold currents as low as 6 mA and 6.2 mW maximum output powers. 2.04-μm-wavelength DFB laser is also described.

Formation of Heterogeneous Thickness Modulations During Epitaxial Growth of LPCVD-Si1−xGex/Si Quantum Well Structures

1992 ◽  
Vol 263 ◽  
Author(s):  
L. Vescan ◽  
W. Jäger ◽  
C. Dieker ◽  
K. Schmidt ◽  
A. Hartmann ◽  
...  
Keyword(s):  
Quantum Well ◽  
Three Dimensional ◽  
Chemical Vapor ◽  
Misfit Dislocations ◽  
Preferential Growth ◽  
Quantum Well Structures ◽  
Transmission Electron ◽  
Pressure Chemical ◽  
Dimensional Growth ◽  
Photoluminescence Studies

ABSTRACTTransmission electron microscopy and photoluminescence studies were performed to determine the critical thickness for generation of misfit dislocations in Sil-xGex layers grown by low pressure chemical vapor deposition. Above a certain Ge content the transition from two dimensional to three-dimensional growth occurs before generation of misfit dislocations. For instance, for x ∼0.3 and a substrate temperature around 700°C island formation was observed to start at 1.8 nm. The formation of islands is attributed to the preferential growth of SiGe in areas with less lattice strain. Islands were observed to broaden the exciton photoluminescence of the quantum well structures.

Growth of Monolayer WS2 Single Crystals with Atmospheric Pressure CVD: Role of Temperature

MRS Advances ◽  
2019 ◽  
Vol 4 (3-4) ◽  
pp. 255-262
Author(s):  
Yong Xie ◽  
Guanfei Wang ◽  
Zhan Wang ◽  
Tang Nan ◽  
Haolin Wang ◽  
...  
Keyword(s):  
Vapor Deposition ◽  
Atmospheric Pressure ◽  
Chemical Vapor ◽  
Optical Microscope ◽  
Nucleation And Growth ◽  
Pressure Chemical ◽  
Different Temperatures ◽  
Individual Domain

ABTRACTIt has been demonstrated that the introduction of NaCl can significantly improve the quality of monolayer WS2 at the growth temperatures ranging from 700°C to 850°C by atmospheric pressure chemical vapor deposition (APCVD) without the assistant of hydrogen. Here, the influence of NaCl on the nucleation and growth of WS2 has been thoroughly investigated. The morphology and quality of WS2 grown with different temperatures are discussed by optical microscope, Raman and Photoluminescence (PL) spectra. It was found that amount of NaCl can efficiently influence the morphology and quality of WS2 crystals. PL intensity of WS2 crystal increases around three times from the center region to the edge of an individual domain, which may be attributed to the appearance of small triangle hollows formed during the growth at the edge of single crystal WS2.

Study of Oxidation Properties of Amorphous Si:B Films

1991 ◽  
Vol 219 ◽  
Author(s):  
G.-R. Yang ◽  
T. C. Nason ◽  
Y.-J. Wu ◽  
B. Y. Tong ◽  
S. K. Wong
Keyword(s):  
Thermal Oxidation ◽  
Boron Content ◽  
Boron Concentration ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Vapor ◽  
Spectroscopic Properties ◽  
Threshold Temperature ◽  
Oxide Layers ◽  
Pressure Chemical ◽  
Secondary Ion

ABSTRACTThin films of an amorphous silicon-boron alloy with boron content 1–50 at.% have been deposited by low pressure chemical vapor deposition (LPCVD). The boron content and film thickness of the samples were controlled by regulating the ratio of diborane and silane gases during the deposition. It was observed that the crystallization of the amorphous alloy took place at higher temperatures as boron concentration was increased. After a thermal oxidation was performed, the stoichiometry of die resulting oxide layers on various samples was determined by the secondary ion mass spectrometry and Auger depth profile methods. While the threshold temperature for thermal oxidation was determined to be inversely proportional to the boron concentration, the oxidation rate showed a dramatic increase with boron content. In particular, an alloy containing 30% boron was readily oxidized at 500°C. Mechanisms for the enhancement of oxidation consistent with stoichiometric and spectroscopic properties of the oxide layers are discussed.

Surfactant-Mediated Growth of SiGe/Si Quantum-Well Structures Studied by Photoluminescence Technique and Secondary Ion Mass Spectrometry

1995 ◽  
Vol 399 ◽  
Author(s):  
S. Nilsson ◽  
H. P. Zeindl ◽  
D. Krüger ◽  
J. Klatt ◽  
R. Kurps
Keyword(s):  
Mass Spectrometry ◽  
Quantum Well ◽  
Secondary Ion Mass Spectrometry ◽  
Near Band Edge ◽  
Single Quantum Well ◽  
Quantum Well Structures ◽  
Ion Mass Spectrometry ◽  
Dimensional Growth ◽  
Temperature Window ◽  
Secondary Ion

ABSTRACTIn this investigation, surfactant-mediated growth of SiGe/Si single quantum-well structures is studied by photoluminescence and secondary ion mass spectrometry. The samples were grown by molecular-beam epitaxy and Sb was used as a surfactant. The photon energy of the SiGe-related near-band-edge photoluminescence was used to probe the action of Sb as a surfactant to promote two-dimensional growth and to reduce segregation of Ge during growth. First, the "growth-temperature window" at which Sb acts preferentially as a surfactant was determined. Then, at this optimized temperature of 700°C, the influence of different Sb coverages was investigated and it was found that 0.5 monolayer was a sufficient coverage to obtain full surfactant action. Ge concentration depth profiles obtained by secondary ion mass spectrometry confirmed the effect of surfactant-mediated growth and, in addition, the unintentional incorporation of the Sb surfactant during growth was determined quantitatively. In a final experiment the effect of deposition of Sb on either the lower or the upper heterointerface is addressed.

Growth of Single-Crystal Pyrite Films by Atmospheric Pressure Chemical Vapor Deposition

2003 ◽  
Vol 15 (9) ◽  
pp. 1763-1765 ◽  
Author(s):  
Naoyuki Takahashi ◽  
Yusuke Nakatani ◽  
Takuma Yatomi ◽  
Takato Nakamura
Keyword(s):  
Chemical Vapor Deposition ◽  
Single Crystal ◽  
Vapor Deposition ◽  
Atmospheric Pressure ◽  
Chemical Vapor ◽  
Pressure Chemical

Growth of Si1−xGex, Strained Layers Using Atmospheric-Pressure CVD

1991 ◽  
Vol 220 ◽  
Author(s):  
F. Namavar ◽  
J. M. Manke ◽  
E. P. Kvam ◽  
M. M. Sanfacon ◽  
C. H. Perry ◽  
...  
Keyword(s):  
Atmospheric Pressure ◽  
Defect Density ◽  
Chemical Vapor ◽  
Good Growth ◽  
X Ray Diffraction ◽  
Strained Layers ◽  
Dislocation Glide ◽  
Transmission Electron ◽  
Pressure Chemical ◽  
Film Defect

ABSTRACTThe objective of this paper is to demonstrate the epitaxial growth of SiGe strained layers using atmospheric-pressure chemical vapor deposition (APCVD). We have grown SiGe layers with various thicknesses and Ge concentrations at temperatures ranging from 800–1000°C. The samples were studied using a variety of methods, including transmission electron microscopy (TEM), high resolution X-ray diffraction (HRXRD) and Raman spectroscopy (RS). Both HRXRD and RS results indicate that samples with about 10% Ge and a thickness of about 1000 Å are almost fully strained. TEM analyses of these samples indicate a film defect density less than 105/cm2. SIMS results indicate that the oxygen concentration in the epitaxial layers is lower than that found in CZ substrates.Our analyses also indicate that as-grown epitaxial Ge layers several microns thick have a defect density less than 107/cm2. The relatively low defect density in both SiGe and Ge layers grown on Si has been attributed to far higher dislocation glide velocity at the relatively elevated growth temperatures employed in CVD and to very good growth cleanliness.

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