Synthesis of Tapered CdS Nanobelts and CdSe Nanowires with Good Optical Property by Hydrogen-Assisted Thermal Evaporation

In this work, the monomer N, N′-bis(4-fluorobenzamide)dicyclohexyl methane (BFDCM) was synthesized successfully by 4-fluorobenzoylchloride and 4,4′-diaminodicyclohexylmethane through interfacial reaction, and then the monomer BFDCM and 1,4-benzenediol (HQ) or 4.4′-biphenol (BH) were used to prepare the novel poly(arylene ether amide) (HQ-BFDCM and BH-BFDCM) containing an aliphatic ring in the main chain by nucleophilic substitution in NMP solution. These two polymers exhibited the inherent viscosities ranging from 0.828 to 1.044 dL g−1, high glass-transition temperatures (Tg) of 214.1–235.0 °C, and weight-loss temperature (T5%) of 425.2–441.3 °C. The polymers HQ-BFDCM and BH-BFDCM could completely or partly dissolve in some polar solutions, such as NMP, DMF, and so on, and they showed moderate corrosion resistance. Additionally, the obtained polymers HQ-BFDCM and BH-BFDCM exhibited good optical property, and the optical transmittances of HQ-BFDCM and BH-BFDCM were 74% and 80% at 450 nm, respectively, which showed that they could be applied to the heat-resistant optical films.

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Optical Property of Spark Plasma Sintered Translucent AlN Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.545 ◽

2007 ◽

Vol 336-338 ◽

pp. 545-548

Author(s):

Y. Xiong ◽

Zheng Yi Fu ◽

Hang Wang

Keyword(s):

Grain Size ◽

Optical Property ◽

Grain Boundaries ◽

Spark Plasma Sintering ◽

Secondary Phases ◽

Fine Grain ◽

Sintering Additive ◽

Plasma Sintering ◽

Spark Plasma ◽

Good Optical Property

Translucent AlN ceramics were fabricated using spark plasma sintering (SPS) technique with 3wt% CaF2 as sintering additive. The samples achieved 52.4% maximum transmittance in medium IR region after 10 min holding time by spark plasma sintering at 1800°C and 30 MPa pressure in N2. The results from XRD, SEM, TEM and EDX showed that the sintered bodies were densely compacted and highly pure with fine grain size and uniform microstructures. No secondary phases were observed at the grain boundaries and triple grain junctions, which guaranteed good optical property of the sintered bodies.

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Microstructural changes of Aluminum Nitride after laser irradiation and electroless copper deposition

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170918 ◽

1994 ◽

Vol 52 ◽

pp. 636-637

Author(s):

S. Cao ◽

A. J. Pedraza ◽

L. F. Allard

Keyword(s):

Aluminum Nitride ◽

Laser Irradiation ◽

Electroless Deposition ◽

Thermal Evaporation ◽

Surface Region ◽

Near Surface ◽

Laser Patterning ◽

Electroless Copper ◽

Excimer Laser Irradiation ◽

Laser Effect

Excimer-laser irradiation strongly modifies the near-surface region of aluminum nitride (AIN) substrates. The surface acquires a distinctive metallic appearance and the electrical resistivity of the near-surface region drastically decreases after laser irradiation. These results indicate that Al forms at the surface as a result of the decomposition of the Al (which has been confirmed by XPS). A computer model that incorporates two opposing phenomena, decomposition of the AIN that leaves a metallic Al film on the surface, and thermal evaporation of the Al, demonstrated that saturation of film thickness and, hence, of electrical resistance is reached when the rate of Al evaporation equals the rate of AIN decomposition. In an electroless copper bath, Cu is only deposited in laser-irradiated areas. This laser effect has been designated laser activation for electroless deposition. Laser activation eliminates the need of seeding for nucleating the initial layer of electroless Cu. Thus, AIN metallization can be achieved by laser patterning followed by electroless deposition.

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Stability Investigation in the Optical Properties of Thermally Evaporated Ge5Se95-x Znx Thin Films

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v7i3.1581 ◽

2015 ◽

Vol 7 (3) ◽

pp. 1923-1930

Author(s):

Austine Amukayia Mulama ◽

Julius Mwakondo Mwabora ◽

Andrew Odhiambo Oduor ◽

Cosmas Mulwa Muiva ◽

Boniface Muthoka ◽

...

Keyword(s):

Thin Films ◽

Band Gap ◽

Optical Band Gap ◽

Thermal Evaporation ◽

Optical Transition ◽

Bulk Material ◽

Band Gap Energy ◽

Optical Absorbance ◽

Gap Energy ◽

Constituent Elements

Â Selenium-based chalcogenides are useful in telecommunication devices like infrared optics and threshold switching devices. The investigated system of Ge5Se95-xZnx (0.0 â‰¤ x â‰¤ 4 at.%) has been prepared from high purity constituent elements. Thin films from the bulk material were deposited by vacuum thermal evaporation. Optical absorbance measurements have been performed on the as-deposited thin films using transmission spectra. The allowed optical transition was found to be indirect and the corresponding band gap energy determined. The variation of optical band gap energy with the average coordination number has also been investigated based on the chemical bonding between the constituents and the rigidity behaviour of the systemâ€™s network.

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Physical and Optical Properties of The Films Ð’i2Te3-Bi2Se3

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v11i2.534 ◽

2015 ◽

Vol 11 (2) ◽

pp. 3017-3022

Author(s):

Gurban Akhmedov

Keyword(s):

Thin Film ◽

Optical Properties ◽

Surface Temperature ◽

Thermal Evaporation ◽

Low Voltage ◽

Internal Surface ◽

Differential Resistance ◽

Work Cycle

Results of researches show, that film p-n the structures received by a method of discrete thermal evaporation in a uniform work cycle, are suitable for use in low-voltage devices.Â As a result of work are received p-n heterojunctions in thin-film execution, described by high values of differential resistance. Show that, thermo endurance - T0 maybe using as characteristic of thermo endurance of optic materials. If heating flow, destruction temperature and internal surface temperature is measured during test, it is possible to determine value T0 and other necessity characteristics. As a result of the taking test was lead to comparison evaluation of considered materials. Working range of heating flow and up level heating embark have been determined.

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Structural and optical properties of Tin Oxide and Indium doped SnO2 thin films deposited by thermal evaporation technique

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v12i3.45 ◽

2016 ◽

Vol 12 (3) ◽

pp. 4394-4399

Author(s):

Sura Ali Noaman ◽

Rashid Owaid Kadhim ◽

Saleem Azara Hussain

Keyword(s):

Thin Films ◽

Optical Properties ◽

Tin Oxide ◽

Thermal Evaporation ◽

Pure Sno2 ◽

X Ray Diffraction ◽

Structural And Optical Properties ◽

X Ray ◽

Evaporation Technique ◽

Sno2 Thin Films

Tin Oxide and Indium doped Tin Oxide (SnO2:In) thin films were deposited on glass and SiliconÂ substratesÂ byÂ thermal evaporation technique.Â X-ray diffraction pattern of Â pure SnO2 and SnO2:In thin films annealed at 650oC and the results showedÂ that the structure have tetragonal phase with preferred orientation in (110) plane. AFM studies showed an inhibition of grain growth with increase in indium concentration. SEM studies of pureÂ SnO2 and Â Indium doped tin oxide (SnO2:In) ) thin films showed that the films with regular distribution of particles and they have spherical shape.Â Optical properties such asÂ Transmission , optical band-gap have been measured and calculated.

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Analysis and optical property modeling of LDEF contaminated chromic acid anodized surfaces

10.2514/6.2000-107 ◽

2000 ◽

Author(s):

S. Woll ◽

V. Loebs ◽

C. Phelps ◽

H. Pippin ◽

D. Grandall ◽

...

Keyword(s):

Optical Property ◽

Chromic Acid ◽

Property Modeling

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Structural, optical and electrical properties of thermal evaporated nano sized In2Te3 thin films

Nanoscale Reports ◽

10.26524/nr1813 ◽

2018 ◽

Vol 1 (1) ◽

pp. 21-25

Author(s):

R Revathi ◽

R Karunathan

Keyword(s):

Thin Films ◽

Negative Temperature Coefficient ◽

Thermal Evaporation ◽

Structural Parameters ◽

Negative Temperature ◽

Resistivity Measurements ◽

Allowed Transition ◽

Evaporation Technique ◽

Indium Telluride ◽

Made In

Indium Telluride thin films were prepared by thermal evaporation technique. Films were annealed at 573K under vacuum for an hour. Both as-deposited and annealed films were used for characterization. The structural parameters were discussed on the basis of annealing effect for a film of thickness 1500 Å. Optical analysis was carried out on films of different thicknesses for both as - deposited and annealed samples. Both the as- deposited and annealed films exhibit direct and allowed transition. Electrical resistivity measurements were made in the temperature range of 303-473 K using Four-probe method. The calculated resistivity value is of the order of 10-6 ohm meter. The activation energy value decreases with increasing film thickness. The negative temperature coefficient indicates the semiconducting nature of the film.

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