TWO DEFECT-RELATED PHOTOLUMINESCENCE SPECTRA AND CROSS-SECTION TEM OF MBE GROWN CdTe ON (100) InSb

1985 ◽  
Vol 56 ◽  
Author(s):  
Z.C. FENG ◽  
A. MASCARENHAS ◽  
W.J. CHOYKE ◽  
R.F.C. FARROW ◽  
J. GREGGI ◽  
...  
Keyword(s):  
Low Temperature ◽  
Substrate Temperature ◽  
Cross Section ◽  
Defect Density ◽  
Luminescence Spectra ◽  
Photoluminescence Spectra ◽  
Region I ◽  
Cdte Films ◽  
Substrate Temperatures ◽  
Region Ii

AbstractA series of MBE grown CdTe films were grown on (100) InSb substrates. The substrate temperature, Ts, was varied from 170° to 285°C in eleven steps. Low temperature (∿2K) photoluminescence measurements and TEM have been combined to show a strong correlation between defect density and the details of the luminescence spectra. A natural division is obtained for samples grown with substrate temperatures from 285°C to 250°C (Region I) and from 225°C to 170°C (Region II).

Properties of Al Films Depend on Substrate Temperature by DC Magnetron Sputter Deposition

2013 ◽  
Vol 662 ◽  
pp. 413-416
Author(s):  
Yi Shen ◽  
Ruo He Yao
Keyword(s):  
Grain Size ◽  
Film Thickness ◽  
Substrate Temperature ◽  
Sheet Resistance ◽  
Cross Section ◽  
Sputter Deposition ◽  
Surface Profiling ◽  
Magnetron Sputter Deposition ◽  
Magnetron Sputter ◽  
Substrate Temperatures

Al films were prepared by DC magnetron sputter deposition at different substrate temperatures. The sheet resistance of the films was measured by four point probe sheet resistance meter, and the film thickness, which was obtained by surface profiling system. The surface and cross-section morphology of the films was observed by AFM and FESEM. As a result, the resistivity of the films decreases obviously as the substrate temperature increases gradually. The higher substrate temperature is, the rougher the films surface is and the larger the grain size is.

SURFACE MORPHOLOGY AND PHOTOLUMINESCENCE CHARACTERISTICS OF Sm-DOPED YVO4 THIN FILMS

2007 ◽  
Vol 14 (05) ◽  
pp. 873-878 ◽  
Author(s):  
HYUN KYOUNG YANG ◽  
JONG WON CHUNG ◽  
BYUNG KEE MOON ◽  
BYUNG CHUN CHOI ◽  
JUNG HYUN JUNG ◽  
...  
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Substrate Temperature ◽  
Photoluminescence Intensity ◽  
Photoluminescence Spectra ◽  
X Ray Diffraction ◽  
Force Microscopy ◽  
Atomic Force ◽  
Zircon Structure ◽  
Substrate Temperatures

Surface morphology and crystallinity of YVO 4: Sm 3+ thin films have an influence on the photoluminescence characteristics. The YVO 4: Sm 3+ films have been deposited on Al 2 O 3 (0001) substrates using pulsed laser deposition method. The films were grown at the various substrate temperatures changing from 500 to 700°C. The crystallinity and surface morphology of the films were investigated using X-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. The results of XRD showed that YVO 4: Sm 3+ films had a zircon structure and AFM study revealed that the films consisted of homogeneous grains ranging from 100 to 400 nm depending on the deposition conditions. The photoluminescence spectra were measured at room temperature and the emitted radiation was dominated by the red emission peak at 620 nm radiated from the transition of 5 D 0-7 F 2. The crystallinity, surface morphology, and photoluminescence spectra of thin-film phosphors were highly dependent on the substrate temperature. The surface roughness and photoluminescence intensity of the films showed similar behavior as a function of substrate temperature.

scholarly journals Формирование кристаллических слоев Cu-=SUB=-2-=/SUB=-O и ZnO методом магнетронного распыления и их оптическая характеризация

2018 ◽  
Vol 52 (3) ◽  
pp. 402
Author(s):  
В.Ф. Агекян ◽  
Е.В. Борисов ◽  
А.С. Гудовских ◽  
Д.А. Кудряшов ◽  
А.О. Монастыренко ◽  
...  
Keyword(s):  
Substrate Temperature ◽  
Oxide Films ◽  
Optical Methods ◽  
Luminescence Spectra ◽  
Zno Films ◽  
X Ray Diffraction ◽  
Zinc Oxide Films ◽  
Quartz Substrates ◽  
Substrate Temperatures

AbstractCopper (I) oxide and zinc oxide films are formed on silicon and glassy quartz substrates by magnetron assisted sputtering. The thickness of the films is tens and hundreds of nanometers. The films are grown at different substrate temperatures and different oxygen pressures in the working chamber. The film samples are studied by the X-ray diffraction technique, scanning electron microscopy, and optical methods. It is established that an increase in the substrate temperature yields a change in the surface morphology of copper (I) oxide films towards the formation of well-pronounced crystallites. The reflectance and Raman spectra suggest that the quality of such films is close to that of bulk Cu_2O crystals produced by the oxidation of copper. As concerns ZnO films, an increase in the substrate temperature and an increase in the partial oxygen pressure make it possible to produce films, for which a sharp exciton structure is observed in the reflectance spectra and the emission of excitons bound at donors is observed in the luminescence spectra.

scholarly journals Correlation between the Low-Temperature Photoluminescence Spectra and Photovoltaic Properties of Thin Polycrystalline CdTe Films

2016 ◽  
Vol 04 (02) ◽  
pp. 391-397
Author(s):  
Bozorboy Joboralievich Akhmadaliev ◽  
Olmos Muhammaddovidovich Mamatov ◽  
Bakhtiyor Zaylobidinovich Polvonov ◽  
Nosirjon Khaydarovich Yuldashev
Keyword(s):  
Low Temperature ◽  
Photoluminescence Spectra ◽  
Photovoltaic Properties ◽  
Cdte Films ◽  
Thin Polycrystalline ◽  
Low Temperature Photoluminescence

A Defect Density of ∼ 1014 cm-3 in Hydrogenated Amorphous Silicon Deposited at High Substrate Temperatures

1992 ◽  
Vol 258 ◽  
Author(s):  
Gautam Ganguly ◽  
Akihisa Matsuda
Keyword(s):  
Substrate Temperature ◽  
Amorphous Silicon ◽  
Deposition Rate ◽  
Defect Density ◽  
Hydrogenated Amorphous Silicon ◽  
High Substrate ◽  
Surface Mobility ◽  
Surface Hydrogen ◽  
Hydrogenated Amorphous ◽  
Substrate Temperatures

ABSTRACTThe idea of surface mobility of growth precursors determined material quality has been exploited by raising the substrate temperature above the conventional 250°C and the ensuing thermal depletion of the surface hydrogen coverage compensated by increasing the precursor flux (deposition rate) to prepare ultra low defect density hydrogenated amorphous silicon.

Observations on the growth of barium bismuth oxide thin films

1992 ◽  
Vol 50 (1) ◽  
pp. 76-77
Author(s):  
M G. Norton ◽  
E.S. Hellman ◽  
E.H. Hartford ◽  
C.B. Carter
Keyword(s):  
Substrate Temperature ◽  
Deposition Process ◽  
Nucleation Layer ◽  
Second Stage ◽  
Device Applications ◽  
High Transition ◽  
Substrate Temperatures ◽  
Oriented Material ◽  
Barium Bismuth ◽  
Superconductor Device

The bismuthates (for example, Ba1-xKxBiO3) represent a class of high transition temperature superconductors. The lack of anisotropy and the long coherence length of the bismuthates makes them technologically interesting for superconductor device applications. To obtain (100) oriented Ba1-xKxBiO3 films on (100) oriented MgO, a two-stage deposition process is utilized. In the first stage the films are nucleated at higher substrate temperatures, without the potassium. This process appears to facilitate the formation of the perovskite (100) orientation on (100) MgO. This nucleation layer is typically between 10 and 50 nm thick. In the second stage, the substrate temperature is reduced and the Ba1-xKxBiO3 is grown. Continued growth of (100) oriented material is possible at the lower substrate temperature.

scholarly journals Crystal mush dykes as conduits for mineralising fluids in the Yerington porphyry copper district, Nevada

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Lawrence C. Carter ◽  
Ben J. Williamson ◽  
Simon R. Tapster ◽  
Catia Costa ◽  
Geoffrey W. Grime ◽  
...  
Keyword(s):  
Low Temperature ◽  
Cross Section ◽  
Porphyry Copper ◽  
Similar Type ◽  
Interconnected Network ◽  
Crystal Mush ◽  
Porphyry Deposit ◽  
Hydrothermal Quartz ◽  
Miarolitic Cavities

AbstractPorphyry-type deposits are the world’s main source of copper and molybdenum and provide a large proportion of gold and other metals. However, the mechanism by which mineralising fluids are extracted from source magmas and transported upwards into the ore-forming environment is not clearly understood. Here we use field, micro-textural and geochemical techniques to investigate field relationships and samples from a circa 8 km deep cross-section through the archetypal Yerington porphyry district, Nevada. We identify an interconnected network of relatively low-temperature hydrothermal quartz that is connected to mineralised miarolitic cavities within aplite dykes. We propose that porphyry-deposit-forming fluids migrated from evolved, more water-rich internal regions of the underlying Luhr Hill granite via these aplite dykes which contained a permeable magmatic crystal mush of feldspar and quartz. The textures we describe provide petrographic evidence for the transport of fluids through crystal mush dykes. We suggest that this process should be considered in future models for the formation of porphyry- and similar-type deposits.

Silicate-germanate K2Y[(Si3Ge)O10(OH)] with unusual complex corrugated layer and its correlation to ring silicate gerenite and chain silicate chkalovite

2020 ◽  
Vol 235 (4-5) ◽  
pp. 167-172
Author(s):  
Anastasiia P. Topnikova ◽  
Elena L. Belokoneva ◽  
Olga V. Dimitrova ◽  
Anatoly S. Volkov ◽  
Leokadiya V. Zorina
Keyword(s):  
Low Temperature ◽  
Cross Section ◽  
Complex Anion ◽  
Diffraction Experiment ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Chain Silicate ◽  
Novel Complex

AbstractA new silicate-germanate K2Y[(Si3Ge)O10(OH)] was synthesized hydrothermally in a system Y2O3:GeO2:SiO2 = 1:1:2 (T = 280 °C; P = 90–100 atm.); K2CO3 was added to the solution as a mineralizer. Single-crystal X-ray diffraction experiment was carried out at low temperature (150 K). The unit cell parameters are a = 10.4975(4), b = 6.9567(2), c = 15.4001(6) Å, β = 104.894(4)°; V = 1086.86(7) Å3; space group is P 21/c. A novel complex anion is presented by corrugated (Si,Ge) tetrahedral layers connected by couples of YO6 octahedra into the mixed microporous framework with the channels along b and a axes, the maximal size of cross-section is ~5.6 Å. This structure has similarity with the two minerals: ring silicate gerenite (Ca,Na)2(Y,REE)3Si6O18 · 2H2O and chain silicate chkalovite Na2BeSi2O6. Six-member rings with 1̅ symmetry as in gerenite are distinguished in the new layer. They are mutually perpendicular to each other and connected by additional tetrahedra. Straight crossing chains in chkalovite change to zigzag four-link chains in the new silicate-germanate layer.

scholarly journals Exciton-Related Raman Scattering, Interband Absorption and Photoluminescence in Colloidal Cdse/Cds Core/Shell Quantum Dots Ensemble

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1274
Author(s):  
Grigor A. Mantashian ◽  
Paytsar A. Mantashyan ◽  
Hayk A. Sarkisyan ◽  
Eduard M. Kazaryan ◽  
Gabriel Bester ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Raman Scattering ◽  
Cross Section ◽  
Core Shell ◽  
Interband Absorption ◽  
Photoluminescence Spectra ◽  
Cds Quantum Dots ◽  
Mass Approximation ◽  
Numerical Discretization ◽  
Size Dispersion

By using the numerical discretization method within the effective-mass approximation, we have theoretically investigated the exciton-related Raman scattering, interband absorption and photoluminescence in colloidal CdSe/CdS core/shell quantum dots ensemble. The interband optical absorption and photoluminescence spectra have been revealed for CdSe/CdS quantum dots, taking into account the size dispersion of the ensemble. Numerical calculation of the differential cross section has been presented for the exciton-related Stokes–Raman scattering in CdSe/CdS quantum dots ensemble with different mean sizes.

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