Optical Properties of (Pb,Eu)Te Thin Films and Superlattices

1986 ◽  
Vol 89 ◽  
Author(s):  
W. C. Goltsos ◽  
A. V. Nurmikko ◽  
D. L. Partin
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spin Exchange ◽  
Optical Measurements ◽  
Optical Gap ◽  
Exchange Processes ◽  
Reflectance Measurements

AbstractPhotoluminescence, transmission, and reflectance measurements have yielded information about the states defining an optical gap in thin films and superlattices based on the (Pb,Eu)Te system, including the limit of high Eu concentration. Magneto-optical measurements show the presence of finite spin exchange processes at low Eu-concentrations.

scholarly journals The physical and optical properties of AZO thin films on teflon substrate at low deposition temperature by spray pyrolysis

2020 ◽  
Vol 18 (3) ◽  
pp. 1222
Author(s):  
Sofea Nabila Hazmin ◽  
F. S. S. Zahid ◽  
N. S. M. Sauki ◽  
M. H. Mamat ◽  
M. N. Amalina
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Spray Pyrolysis ◽  
Deposition Temperature ◽  
Spray Pyrolysis Technique ◽  
Optical Measurements ◽  
Physical Analysis ◽  
X Ray Diffraction ◽  
Visible Reflectance ◽  
Low Deposition Temperature

<span>This paper presents the physical and optical properties of AZO thin films on Teflon substrate at low deposition temperature by spray pyrolysis. In this study, the effect of different process parameters such as spray time and substrate to nozzle distance on the physical and optical characteristic of aluminium doped zinc oxide (AZO) deposited on Teflon substrates was investigated. The AZO thin films were successfully deposited onto Teflon substrate by spray pyrolysis technique at low deposition temperature. The physical analysis by X-ray diffraction (XRD) shows that the deposited Teflon substrate films have a preferred orientation along the direction (100) and (101). Optical measurements were conducted using Jasco/V-670 Ex Uv-Vis-NIR Spectrophotometer model to confirms that in visible ray it is possible to get good reflectance of AZO films with a reflection of 80%. The values of band gaps Eg were calculated from the spectra of UV-Visible reflectance that were vary between 3.06 and 3.14 eV. </span>

Nanoporous Ceria Films Prepared from Colloidal Suspension

2000 ◽  
Vol 654 ◽  
Author(s):  
Vladimir Petrovsky ◽  
Brian Gorman ◽  
Harlan U. Anderson ◽  
Tatiana Petrovsky
Keyword(s):  
Grain Size ◽  
Optical Properties ◽  
Band Gap ◽  
Colloidal Suspension ◽  
Colloidal Suspensions ◽  
Band Gap Energy ◽  
Optical Measurements ◽  
Optical Spectrophotometry ◽  
Reflectance Measurements ◽  
Good Agreement

AbstractThe influence of porosity and densification on optical properties of films on sapphire substrates that were prepared from water colloidal suspensions of small (∼5nm) particles of ceria was investigated. The colloidal ceria films have initially very porous structure (porosity about 50%) and densification starts at about 600°oC accompanied by grain growth. The concurrence of these two processes makes it difficultto interpret the results of the optical spectrophotometry, but the combination of transmittance and reflectance measurements provides enough data to separate these two influences and to calculate the porosity, particlesize and energy band gap separately. XRD, SEM, ellipsometry and mechanical profilometry were used to confirm the results obtained from the specrophotometric measurements. All these methods gave results, which are in good agreement: the change in the porosity from 50% to 15% and the particle size increased from 5 to 65nm in the temperature region from 400 to 1000°oC. An important result of the investigation is the fact that the main optical properties of the coating such as refractive index and band gap energy depend only on the porosity, but not on the grain size. The grain size influences the scattering properties of the coating, which allows the grain size to be estimated from optical measurements.

CHARACTERIZATION OF AlN THIN FILMS FABRICATED BY REACTIVE DC SPUTTERING: EXPERIMENTAL MEASUREMENTS AND HÜCKEL CALCULATIONS

2009 ◽  
Vol 23 (09) ◽  
pp. 2233-2251 ◽  
Author(s):  
MANUEL GARCÍA-MÉNDEZ ◽  
SANTOS MORALES-RODRÍGUEZ ◽  
DONALD H. GALVÁN ◽  
ROBERTO MACHORRO
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Optical Measurements ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
Zinc Blende ◽  
Single Oscillator ◽  
Effect Of Oxygen ◽  
Oxygen Impurities

A set of AlN thin films was prepared by reactive magnetron sputtering at room temperature. The effect of oxygen impurities on the structural and optical properties of AlN films is discussed. The structural and optical properties were characterized using X-ray diffraction (XRD) and spectroscopic ellipsometry, respectively. Depending on the deposition conditions, films can grow hexagonal (würzite, P 63 m 3) or cubic (zinc-blende, Fm3m) in microstructure. From the optical measurements, the ellipsometric parameters (ψ, Δ) and the real refractive index as a function of energy were obtained. From the ellipsometric measurements, a model of Lorentz single-oscillator was employed to estimate the optical band gap, Eg. In the theoretical part, a calculation of density of states (DOS) and band structure was performed to be compared with the experimental results.

Effect of Hydrogenation on Structural, Optical and Electrical Properties of Amorphous InAsSb Thin Films

2010 ◽  
Vol 160-162 ◽  
pp. 1508-1512
Author(s):  
Yan Ping Yao ◽  
Chun Ling Liu ◽  
Hai Dong Qi ◽  
Xi Chang ◽  
Chun Wu Wang
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Electrical Properties ◽  
Optical Absorption ◽  
Rf Magnetron Sputtering ◽  
Dark Conductivity ◽  
Optical And Electrical Properties ◽  
Optical Absorption Edge ◽  
Hydrogen Addition ◽  
Optical Gap

Amorphous InAsSb films and hydrogenated InAsSb films are deposited on substrates of quartz glass and silicon by rf magnetron sputtering technique in different gas ambient. The effect of H addition on structure, optical properties and electrical properties of a-InAsSb is studied. It is found that the bonded hydrogen content increases with increasing H2 to Ar flow rate radio(R). When R is 0.1, Hydrogen addition shifts the optical absorption edge to higher energy, decreases the dark conductivity and improves the photo-sensitivity. However, hydrogen addition produces the crystallization of the film at R>0.1. Moreover the optical gap, dark conductivity and photo-sensitivity of the films have a reverse change compared with that in R=0. These results demonstrate that hydrogen has obvious passivation effects on rf sputtered amorphous InAsSb thin films only at R=0.1.

scholarly journals Effect of iron doping on structural and optical properties of TiO2 thin film by sol–gel routed spin coating technique

2017 ◽  
Vol 07 (04) ◽  
pp. 1750024 ◽  
Author(s):  
Stephen Lourduraj ◽  
Rayar Victor Williams
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Optical Properties ◽  
Spin Coating ◽  
Sol Gel ◽  
Visible Region ◽  
Spin Coating Technique ◽  
Optical Measurements ◽  
Structural And Optical Properties ◽  
Coating Technique

Thin films of iron (Fe)-doped titanium dioxide (Fe:TiO[Formula: see text] were prepared by sol–gel spin coating technique and further calcined at 450[Formula: see text]C. The structural and optical properties of Fe-doped TiO2 thin films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV–vis) and atomic force microscopic (AFM) techniques. The XRD results confirm the nanostructured TiO2 thin films having crystalline nature with anatase phase. The characterization results show that the calcined thin films having high crystallinity and the effect of iron substitution lead to decreased crystallinity. The SEM investigations of Fe-doped TiO2 films also gave evidence that the films were continuous spherical shaped particles with a nanometric range of grain size and film was porous in nature. AFM analysis establishes that the uniformity of the TiO2 thin film with average roughness values. The optical measurements show that the films having high transparency in the visible region and the optical band gap energy of Fe-doped TiO2 film with iron (Fe) decrease with increase in iron content. These important requirements for the Fe:TiO2 films are to be used as window layers in solar cells.

scholarly journals Optical Properties for SeTe Thin Films

2008 ◽  
Vol 5 (4) ◽  
pp. 577-580
Author(s):  
Baghdad Science Journal
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Chalcogenide Glasses ◽  
Thermal Evaporation ◽  
Energy Gap ◽  
Glass Substrates ◽  
Optical Gap ◽  
Varying Thickness ◽  
Amorphous Nature ◽  
Constituent Elements

Chalcogenide glasses SeTe have been prepared from the high purity constituent elements .Thin films of SeTe compound have been deposited by thermal evaporation onto glass substrates for different values of film thickness . The effect of varying thickness on the value of the optical gap is reported . The resultant films were in amorphous nature . The transmittance spectra was measured for that films in the wavelength range (400-1100) nm . The energy gap for such films was determined .

EFFECT OF ANNEALING TEMPERATURE ON OPTICAL PROPERTIES OF TITANIUM DIOXIDE THIN FILMS PREPARED BY SOL-GEL METHOD

2011 ◽  
Vol 25 (31) ◽  
pp. 4163-4166 ◽  
Author(s):  
M. T. SARODE ◽  
P. N. SHELKE ◽  
Y. B. KHOLLAM ◽  
S. R. JADKAR ◽  
B. B. KALE ◽  
...  
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Band Gap ◽  
Annealing Temperature ◽  
Anatase Phase ◽  
Sol Gel ◽  
Nanocrystalline Structure ◽  
Dip Coating ◽  
Optical Measurements ◽  
Crystallite Sizes

TiO 2 sol-gel thin films were deposited on glass substrates by dip coating method. Nanocrystalline TiO 2 thin films were prepared at 300°C. The effect of annealing temperature on optical properties of nanocrystalline TiO 2 thin films was studied. The films were characterized by different techniques: XRD, UV-visible spectroscopy, FTIR spectroscopy and FESEM. The characterization studies revealed that the films are crystallized as anatase phase and are nano-structured. The optical measurements were showed the indirect band gap between 3.31 and 3.35 eV with corresponding crystallite sizes between 8.9 and 3.7 nm at the temperatures 300, 400 and 500°C. The FESEM images of film were showed spherical nanocrystalline structure of TiO 2 particles with the crystallite sizes between 30 and 100 nm. It is also observed that refractive index of the film increases with increasing the annealing temperature. The smaller crystallite size gives larger band gap due to quantum size effects.

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