Room‐temperature excitonic optical nonlinearities of molecular beam epitaxially grown ZnSe thin films

1988 ◽  
Vol 52 (3) ◽  
pp. 182-184 ◽  
Author(s):  
N. Peyghambarian ◽  
S. H. Park ◽  
S. W. Koch ◽  
A. Jeffery ◽  
J. E. Potts ◽  
...  
Keyword(s):  
Thin Films ◽  
Room Temperature ◽  
Molecular Beam ◽  
Optical Nonlinearities ◽  
Znse Thin Films

Electrical Properties of Nanostructure n-ZnSe/p-Si(100) Heterojunction Thin Film Diode

2018 ◽  
Vol 775 ◽  
pp. 246-253
Author(s):  
Ngamnit Wongcharoen ◽  
Thitinai Gaewdang
Keyword(s):  
Thin Films ◽  
Ideality Factor ◽  
Room Temperature ◽  
Energy Levels ◽  
Thermionic Emission ◽  
Depletion Region ◽  
Trap Level ◽  
Characteristic Energy ◽  
Znse Thin Films

The ZnSe/Si heterojunction is of specific interest since this structure provides effective solar cell and enables the integration of wide bandgap device in silicon circuits. It is known that the quality of the diode and the current transport mechanisms across the heterojunction may be greatly influenced by the quality of the interface and depends on the crystallinity of the film layer. In this work, n-ZnSe/p-Si (100) heterojunction was fabricated by thermal evaporating ZnSe thin films on p-Si (100) substrates. The current-voltage characteristics of n-ZnSe/p-Si (100) heterojunction were investigated in temperature range 20-300 K. Some important parameters such as barrier height, ideality factor and series resistance values evaluated by using thermionic emission (TE) theory and Cheung’s method at room temperature are n = 2.910,φB0= 0.832 eV and 8.59103Ω, respectively. The temperature dependence of the saturation current and ideality factor are well described by tunneling enhanced recombination at junction interface with activation energy and characteristic energy values about 1.293 eV and E00= 95 meV, respectively. The carrier concentration of ZnSe thin films about 3.16×1013cm-3was deduced from the C-V measurements at room temperature. Admittance spectroscopy was employed for analysis of the defect energy levels situated in depletion region. The results showed that there was a single trap level whose position in the band gap was close to 0.04 eV above valence band. The results of this work may be useful for application such as heterojunction solar cells.

Effect of pH on the structural and optical properties of polycrystalline ZnSe thin films produced by CBD method

2019 ◽  
Vol 33 (05) ◽  
pp. 1950024 ◽  
Author(s):  
Fatma Meydaneri Tezel ◽  
İ. Afşin Kariper
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Room Temperature ◽  
Dielectric Constants ◽  
Structural And Optical Properties ◽  
Polycrystalline Structure ◽  
Density Values ◽  
Cbd Method ◽  
Znse Thin Films ◽  
Absorbance Spectra

In this study, zinc selenide (ZnSe) thin films were produced on glass substrate by using chemical bath deposition (CBD) method at 80[Formula: see text]C, from aqueous solutions of zinc sulphate and sodium selenosulphide, which were produced using solid selenium as the selenium source. The optical and structural properties of ZnSe thin films were investigated at room-temperature. The pH of the chemical bath, in which ZnSe thin films were immersed, were changed between pH:8–11. Optical properties of the films, including extinction coefficient, refractive index, reflectance, absorbance, transmittance, dielectric constants and optical density values were calculated using absorbance and transmittance measurements determined using a Hach Lange 500 spectrophotometer, in 300–1100 nm wavelength range. Optical bandgap values were obtained from transmittance and absorbance spectra ranged between 2.12 and 2.49 eV. According to XRD results, it was found that the films have polycrystalline structure and they exhibited different film thicknesses depending on phase and pH changes.

scholarly journals Origin of Ultraviolet Luminescence from Bulk ZnO Thin Films Grown by Molecular Beam Epitaxy

2011 ◽  
Vol 1 ◽  
pp. 135-139 ◽  
Author(s):  
M. Asghar ◽  
Khalid Mahmood ◽  
Adnan Ali ◽  
M.A. Hasan ◽  
I. Hussain ◽  
...  
Keyword(s):  
Thin Films ◽  
Raman Spectroscopy ◽  
Molecular Beam Epitaxy ◽  
Room Temperature ◽  
Molecular Beam ◽  
Energy Dispersive ◽  
Zno Thin Films ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Luminescence

Origin of ultraviolet (UV) luminescence from bulk ZnO has been investigated with the help of photoluminescence (PL) measurements. Thin films of ZnO having 52%, 53% and 54% of Zn-contents were prepared by means of molecular beam epitaxy (MBE). We observed a dominant UV line at 3.28 eV and a visible line centered at 2.5 eV in the PL spectrum performed at room temperature. The intensity of UV line has been found to depend upon the Zn percentage in the ZnO layers. Thereby, we correlate the UV line in our samples with the Zn-interstitials-bound exciton (Zni-X) recombination. The results obtained from, x-ray diffraction, the energy dispersive X-ray spectrum (EDAX) and Raman spectroscopy supported the PL results.

scholarly journals Nonradiative Carrier Recombination in p-Type ZnSe Thin Films Grown by Molecular Beam Epitaxy

1999 ◽  
Vol 211 (2) ◽  
pp. 885-885
Author(s):  
K. Yoshino ◽  
Y. Nakagawa ◽  
A. Fukuyama ◽  
H. Yokoyama ◽  
K. Maeda ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Carrier Recombination ◽  
Znse Thin Films ◽  
P Type

scholarly journals Formation of ferromagnetic molecular thin films from blends by annealing

2017 ◽  
Vol 8 ◽  
pp. 1469-1475 ◽  
Author(s):  
Peter Robaschik ◽  
Ye Ma ◽  
Salahud Din ◽  
Sandrine Heutz
Keyword(s):  
Thin Films ◽  
Curie Temperature ◽  
Room Temperature ◽  
Molecular Beam ◽  
Size Mismatch ◽  
New Approach ◽  
Molecular Beam Deposition ◽  
Molecular Thin Films ◽  
Beam Deposition

We report on a new approach for the fabrication of ferromagnetic molecular thin films. Co-evaporated films of manganese phthalocyanine (MnPc) and tetracyanoquinodimethane (TCNQ) have been produced by organic molecular beam deposition (OMBD) on rigid (glass, silicon) and flexible (Kapton) substrates kept at room temperature. The MnPc:TCNQ films are found to be entirely amorphous due to the size mismatch of the molecules. However, by annealing while covering the samples highly crystalline MnPc films in the β-polymorph can be obtained at 60 °C lower than when starting with pure MnPc films. The resulting films exhibit substantial coercivity (13 mT) at 2 K and a Curie temperature of 11.5 K.

scholarly journals Half-metals and half-semiconductors in a transition metal doped SnSe2 monolayer: a first-principles study

RSC Advances ◽  
2017 ◽  
Vol 7 (70) ◽  
pp. 44499-44504 ◽  
Author(s):  
Xuming Wu ◽  
Jiangchao Han ◽  
Yulin Feng ◽  
Guanpeng Li ◽  
Cong Wang ◽  
...  
Keyword(s):  
Thin Films ◽  
First Principles ◽  
Room Temperature ◽  
Molecular Beam ◽  
Ferromagnetic Behavior ◽  
Two Dimensional ◽  
Half Metals ◽  
Metal Doped ◽  
Mn Doped ◽  
Weak Ferromagnetic

Recently, a new two-dimensional (2D) semiconductor SnSe2 monolayer has been grown by molecular beam epitaxy, and weak ferromagnetic behavior above room temperature in Mn-doped SnSe2 thin films was also observed experimentally.

Spectroscopic studies of molecular-beam epitaxially grown Cr2+-doped ZnSe thin films

2005 ◽  
Vol 86 (9) ◽  
pp. 091105 ◽  
Author(s):  
A. Gallian ◽  
V. V. Fedorov ◽  
J. Kernal ◽  
J. Allman ◽  
S. B. Mirov ◽  
...  
Keyword(s):  
Thin Films ◽  
Molecular Beam ◽  
Spectroscopic Studies ◽  
Znse Thin Films
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