scholarly journals Effects of Temperature on the Structural and Optical Preperties of AgGaSe2 Thin Films

1970 ◽  
Vol 33 (2) ◽  
pp. 179-188
Author(s):  
MRA Bhuiyan ◽  
DK Saha ◽  
SM Firoz Hasan
Keyword(s):  
Thin Films ◽  
Annealing Temperature ◽  
Visible Region ◽  
Wavelength Region ◽  
Band Gap Energy ◽  
Post Deposition Annealing ◽  
X Ray ◽  
Glass Substrates ◽  
Academy Of Sciences ◽  
Post Deposition

In this study, AgGaSe2 (AGS) thin films were formed onto cleaned glass substrates by using the stacked elemental layer (SEL) deposition technique in vacuum. The films were prepared at the post-deposition annealing temperature from 100 to 350°C for 15 min duration. The atomic composition of the films was measured by energy dispersive analysis of X-ray (EDAX) method. The films ascertain the compositional uniformity. The X-ray diffraction (XRD) has been employed to study the structure of the films. The structures of the films are found to be polycrystalline in nature. The lattice parameters, grain size, strain and dislocation densities of the films were calculated. Optical characteristics of the films were ascertained by spectrophotometer in the photon wavelength ranging between 300 and 2500 nm. The transmittance was found to increase with the increase of annealing temperature. The transmittance falls steeply with decreasing wavelength. It revealed that AGS films have considerable absorption throughout the wavelength region from 400 to 800 nm. The optical band gap energy has been evaluated. Two possible direct allowed and direct forbidden transitions have been observed for all the AGS films in visible region. The former varied from 1.67 to 1.75 eV and the later from 2.05 to 2.08 eV, depending on the post-deposition annealing temperature of the films. DOI: 10.3329/jbas.v33i2.4101 Journal of Bangladesh Academy of Sciences, Vol. 33, No. 2, 179-188, 2009

scholarly journals Studies on the Electrical and Optical Properties of Magnesium Phthalocyanine Thin Films

2004 ◽  
Vol 1 (5) ◽  
pp. 231-236
Author(s):  
T. G. Gopinathan ◽  
C. S. Menon
Keyword(s):  
Thin Films ◽  
Electrical Conductivity ◽  
Visible Region ◽  
Absolute Temperature ◽  
Post Deposition Annealing ◽  
Glass Substrates ◽  
Absorption Studies ◽  
Evaporation Technique ◽  
Uv Visible ◽  
Post Deposition

Thin films of Magnesium Phthalocyanine (MgPc) are prepared by thermal evaporation technique at a base pressure of 10-5m.bar on thoroughly cleaned glass substrates kept at different constant temperatures. Films of thickness 2400 A.U. coated at room temperature are subjected to post deposition annealing in air by keeping them in a furnace at different constant temperatures, for one hour. The electrical conductivity studies are conducted in the temperature range 300 K to 525 K. The electrical conductivity is plotted as a function of absolute temperature. The conduction mechanism is observed to be hopping. The thermal activation energy is calculated in different cases and is observed to vary with substrate temperature and annealing temperature. A phase change is observed due to post-deposition annealing at around 523 K. The optical absorption studies are done in the UV-Visible region. The optical band gap energies of the samples are calculated.

scholarly journals Effect of Annealing on the Nanostructure Formation in Alkoxy Substituted Phthalocyanine Thin Films

2012 ◽  
Vol 9 (4) ◽  
pp. 1992-1999
Author(s):  
Vinu. T. Vadakel ◽  
C. S. Menon
Keyword(s):  
Thin Films ◽  
Band Gap ◽  
Annealing Temperature ◽  
Optical Band Gap ◽  
Band Gap Energy ◽  
Sem Images ◽  
Glass Substrates ◽  
Heat Treated ◽  
Different Temperatures ◽  
Post Deposition

Vacuum deposited 2,3,9,10,16,17,23,24-octakis (octyloxy) phthalocyanine (H2PcOC8) thin films on glass substrates have exhibited a change on their surface morphology with the post deposition annealing temperature under normal atmosphere. These films have been characterized by optical absorptions and Scanning Electron Microscopy. SEM images also have shown nano-rod like structures for the samples annealed at different temperatures. The variation of optical band gap with annealing temperature is determined. The direct and allowed optical band gap energy has been evaluated from the α2versus hυ plots. The electrical conductivity of the films at various heat treated samples are also studied. The activation energies are determined from the Arrhenius plots of lnσ versus 1000/T . It shows variation with the annealing temperature.

Effect of vacuum annealing on the properties of one step thermally evaporated Sb2S3 thin films for photovoltaic applications

2021 ◽  
Author(s):  
Emna Gnenna ◽  
Naoufel Khemiri ◽  
Minghua Kong ◽  
Maria Isabel Alonso ◽  
Mounir Kanzari
Keyword(s):  
Thin Films ◽  
Annealing Temperature ◽  
Vacuum Annealing ◽  
Xrd Analysis ◽  
Band Gap Energy ◽  
Chemical Compositions ◽  
Optical Parameters ◽  
X Ray ◽  
Vis Spectroscopy ◽  
One Step

Sb2S3 powder was successfully synthesized by solid state reaction technique using high-purity elemental antimony and sulfur. Sb2S3 thin films were deposited on unheated glass substrates by one step thermal evaporation and annealed under vacuum atmosphere for 2 hours at different temperatures 150, 200 and 250 °C. Different characterization techniques were used to better understand the behavior of the Sb2S3 material. X-ray diffraction (XRD) and Raman spectroscopy confirmed the formation of pure Sb2S3 powder with lattice parameters a = 11.07 Å, b = 11.08 Å and c = 3.81 Å. The effect of vacuum annealing temperature on the properties of the films was studied. XRD analysis revealed that as-deposited and annealed films at 150ºC were amorphous in nature whereas those annealed at T ≥ 200°C were polycrystalline with a preferred orientation along (201) plane. The crystallite size of the polycrystalline films showed a decrease from 75.8 to 62.9 nm with the increase of the annealing temperature from 200 to 250 °C. The Raman analysis showed several peaks corresponding to the stibnite Sb2S3 phase. The surface morphology of the films was examined by atomic force microscopy (AFM). The surface roughness decreases slightly as the transformation from the amorphous to the crystalline phase occurs. The chemical compositions of Sb2S3 films were analyzed by energy dispersive X-ray spectroscopy (EDS), revealing that all films were Sb-rich. The optical parameters were estimated from the transmittance and reflectance spectra recorded by UV-Vis spectroscopy. A reduction in the direct band gap energy from 2.12 to 1.70 eV with the increase of annealing temperature was also found.

INVESTIGATING ANNEALING EFFECT ON OPTICAL PROPERTIES OF Cd0.8Zn0.2S THIN FILMS

2014 ◽  
Vol 21 (05) ◽  
pp. 1450073 ◽  
Author(s):  
SOMAYEH AZIZI ◽  
HAMID REZAGHOLIPOUR DIZAJI ◽  
MOHAMMAD HOSSEIN EHSANI ◽  
SEYED FEYZOLAH GHAVAMI MIRMAHALLE
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Hexagonal Wurtzite Structure ◽  
Band Gap Energy ◽  
Annealing Effect ◽  
Thin Layers ◽  
Optical Parameters ◽  
Thermal Evaporation Method ◽  
X Ray ◽  
Glass Substrates

Cd 0.8 Zn 0.2 S thin films deposited on glass substrates by thermal evaporation method were annealed at different temperatures for the first time in order to investigate annealing effect on optical properties. The compositional, structural of nanoparticles precursor synthesized using microwave irradiation method and optical properties of the films were studied using energy dispersive X-ray (EDX), X-ray diffraction, transmission electron microscopy (TEM), and UV-visible spectrophotometer techniques. The annealed films were found to have hexagonal Wurtzite structure with strong preferential orientation along the (002) diffraction peak. Important optical parameters such as extinction coefficient and refractive index revealed the effect of heat treatment on the deposited thin layers. A reduction in the band gap energy from 2.41 eV to 2.29 eV was observed for the annealed samples.

Structural Properties of Ag-Based Chalcopyrite Compound Thin Films for Solar Cells

2005 ◽  
Vol 865 ◽  
Author(s):  
Hiroki Ishizaki ◽  
Keiichiro Yamada ◽  
Ryouta Arai ◽  
Yasuyuki Kuromiya ◽  
Yukari Masatsugu ◽  
...  
Keyword(s):  
Thin Films ◽  
Rietveld Analysis ◽  
Atomic Ratio ◽  
Band Gap Energy ◽  
X Ray Diffraction ◽  
Structural And Optical Properties ◽  
X Ray ◽  
Glass Substrates ◽  
Crystallographic Property ◽  
Chalcopyrite Compound

AbstractAgGa5Se8 and Ag(In1-xGax)Se2 thin films with different Ag/Ga atomic ratios have been deposited on the corning 1737 glass substrates by molecular beam epitaxy (MBE) system. This crystallographic property of AgGa5Se8 thin films has been investigated by x-ray diffraction and rietveld analysis. These films had the tetragonal structure with the space group of P-42m, regardless of Ag/Ga atomic ratio. The lattice parameters and the optical band gap energy decreased with an increase in the Ag/Ga atomic ratio. Thus, the structural and optical properties of these AgGa5Se8 thin films were controlled by the Ag/Ga atomic ratio.

scholarly journals Influence of annealing temperature on the sensitivity of nickel oxide nanosheet films in humidity sensing applications

2020 ◽  
Vol 18 (1) ◽  
pp. 284
Author(s):  
N. Parimon ◽  
M. H. Mamat ◽  
A. S. Ismail ◽  
I. B. Shameem Banu ◽  
M. K. Ahmad ◽  
...  
Keyword(s):  
Nickel Oxide ◽  
Annealing Temperature ◽  
Sol Gel ◽  
Visible Region ◽  
Annealed Film ◽  
Band Gap Energy ◽  
Humidity Sensing ◽  
Glass Substrates ◽  
Sensing Applications ◽  
Vis Spectroscopy

Nickel oxide (NiO) nanosheet films were successfully grown onto NiO seed-coated glass substrates at different annealing temperatures for humidity sensing applications. NiO seed layers and NiO nanosheet films were prepared using a sol-gel spin coating and sonicated sol-gel immersion techniques, respectively. The properties of NiO nanosheet films at as-deposited, 300 ℃, and 500 ℃-annealed were examined by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible (UV-vis) spectroscopy, and humidity sensor measurement system. The XRD patterns demonstrate that the grown NiO films have crystalline cubic structures at temperature of 300 ℃ and 500 ℃. The FESEM images show that the large porous nanosheet network spread over the layers as the annealing temperature increased. The UV-vis spectra revealed that all the nanosheet films have the average transmittance below than 50% in the visible region, with absorption edges ~ 350 nm. The optical band gap energy was evaluated in ranges of 3.39 to 3.61 eV. From the obtained humidity sensing results, it shows that 500 ℃-annealed film exhibited the best sensitivity of 257, as well as the slowest response time, and the fastest recovery time compared with others.

scholarly journals Annealing-Driven Microstructural Evolution and Its Effects on the Surface and Nanomechanical Properties of Cu-Doped NiO Thin Films

Coatings ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 107 ◽  
Author(s):  
San-Ho Wang ◽  
Sheng-Rui Jian ◽  
Guo-Ju Chen ◽  
Huy-Zu Cheng ◽  
Jenh-Yih Juang
Keyword(s):  
Thin Films ◽  
Photoelectron Spectroscopy ◽  
Annealing Temperature ◽  
Film Surface ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nanomechanical Properties ◽  
Glass Substrates ◽  
Structural Surface ◽  
Diffraction Peaks

The effects of annealing temperature on the structural, surface morphological and nanomechanical properties of Cu-doped (Cu-10 at %) NiO thin films grown on glass substrates by radio-frequency magnetron sputtering are investigated in this study. The X-ray diffraction (XRD) results indicated that the as-deposited Cu-doped NiO (CNO) thin films predominantly consisted of highly defective (200)-oriented grains, as revealed by the broadened diffraction peaks. Progressively increasing the annealing temperature from 300 to 500 °C appeared to drive the films into a more equiaxed polycrystalline structure with enhanced film crystallinity, as manifested by the increased intensities and narrower peak widths of (111), (200) and even (220) diffraction peaks. The changes in the film microstructure appeared to result in significant effects on the surface energy, in particular the wettability of the films as revealed by the X-ray photoelectron spectroscopy and the contact angle of the water droplets on the film surface. The nanoindentation tests further revealed that both the hardness and Young’s modulus of the CNO thin films increased with the annealing temperature, suggesting that the strain state and/or grain boundaries may have played a prominent role in determining the film’s nanomechanical characterizations.

scholarly journals Properties of Thin Film-Covered GaN(0001) Surfaces

2020 ◽  
Vol 2 (1) ◽  
pp. 30
Author(s):  
Miłosz Grodzicki
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Surface Properties ◽  
Vapour Deposition ◽  
Metal Films ◽  
Physical Vapour Deposition ◽  
Surface Alloying ◽  
Post Deposition Annealing ◽  
X Ray ◽  
Post Deposition

In this paper, the surface properties of bare and film-covered gallium nitride (GaN) of the wurtzite form, (0001) oriented are summarized. Thin films of several elements—manganese, nickel, arsenic and antimony—are formed by the physical vapour deposition method. The results of the bare surfaces as well as the thin film/GaN(0001) phase boundaries presented are characterized by X-ray and ultraviolet photoelectron spectroscopies (XPS, UPS). Basic information about electronic properties of GaN(0001) surfaces are shown. Different behaviours of thin films after post-deposition annealing in ultrahigh vacuum conditions, such as surface alloying, subsurface dissolving and desorbing, are found. The metal films form surface alloys with gallium (NiGa, MnGa), while the semi-metal (As, Sb) layers easily evaporate from the GaN(0001) surface. However, the layer in direct contact with the substrate can react with it modifying the surface properties of GaN(0001).

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