Electrical and Optical Properties of :H Thin Films Prepared by Thermal Evaporation Method

Thin a-:H films were grown successfully by fabrication of designated ingot followed by evaporation onto glass slides. A range of growth conditions, Ge contents, dopant concentration (Al and As), and substrate temperature, were employed. Stoichiometry of the thin films composition was confirmed using standard surface techniques. The structure of all films was amorphous. Film composition and deposition parameters were investigated for their bearing on film electrical and optical properties. More than one transport mechanism is indicated. It was observed that increasing substrate temperature, Ge contents, and dopant concentration lead to a decrease in the optical energy gap of those films. The role of the deposition conditions on values of the optical constants was determined. Accordingly, models of the density of states for the :H thin films as pure, doped with 3.5% of Al (p-type) and that doped with 3.5% As (n-type), were proposed.

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Study Influence of Substrate Temperature on Optical Properties of CdS Thin Films Prepared by Chemical Spray pyrolysis

Ibn AL- Haitham Journal For Pure and Applied Science ◽

10.30526/32.1.1982 ◽

2019 ◽

Vol 32 (1) ◽

pp. 6 ◽

Cited By ~ 2

Author(s):

Karrar Mahdi Saleh

Keyword(s):

Thin Films ◽

Optical Properties ◽

Substrate Temperature ◽

Spray Pyrolysis ◽

Energy Gap ◽

Nitrate Solution ◽

Chemical Spray Pyrolysis ◽

Optical Energy Gap ◽

Chemical Spray ◽

Cds Thin Films

This study aims to prepare Cadmium Sulphide (CdS) thin films using thermal Chemical Spray Pyrolysis (CSP) on glass of different temperatures substrate from cadmium nitrate solution. Constant thickness was (430 ± 20 nm) and the effect of substrate temperature on the optical properties of prepared thin films. Optical properties have been studied from transmittance and absorbance spectral within wavelengths range (360 - 900 nm). The results show that all the prepared films have a direct electron transitions and optical energy gap between (2.31-2.44 eV). They also show that the transmittance and optical energy gap of films prepared from nitrate solution increase with increasing of substrate temperature, then transmittance start downward with the continued increase in temperature (400, 450) oC.

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The structure and optical properties of CdSe:Cu Thin Films

Baghdad Science Journal ◽

10.21123/bsj.6.1.141-149 ◽

2009 ◽

Vol 6 (1) ◽

pp. 141-149

Author(s):

Baghdad Science Journal

Keyword(s):

Thin Films ◽

Optical Properties ◽

Absorption Coefficient ◽

Substrate Temperature ◽

Energy Gap ◽

Hexagonal Structure ◽

X Ray Diffraction ◽

Optical Energy Gap ◽

X Ray ◽

Substrate Temperatures

A polycrystalline CdSe thin films doped with (5wt%) of Cu was fabricated using vacuum evaporation technique in the substrate temperature range(Ts=RT-250)oC on glass substrates of the thickness(0.8?m). The structure of these films are determined by X-ray diffraction (XRD). The X-ray diffraction studies shows that the structure is polycrystalline with hexagonal structure, and there are strong peaks at the direction (200) at (Ts=RT-150) oC, while at higher substrate temperature(Ts=150-250) oC the structure is single crystal. The optical properties as a function of Ts were studied. The absorption, transmission, and reflection has been studied, The optical energy gap (Eg)increases with increase of substrate temperature from (1.65-1.84)eV due to improvement in the structure. The amorphousity of the films decreases with increasing Ts. The films have direct energy gap and the absorption edge was shift slightly towards smaller wavelength for CdSe:Cu thin film with increase of substrate temperature.it was found that the absorption coefficient was decreased with increasing of substrate temperature due to increases the value of(Eg). The CdSe:Cu films showed absorption coefficient in the range (0.94 x104-0.42x104)cm-1at Ts=RT-250 oC. Also the density of state decreases with increasing of substrate temperatures from (0.20-0.07)eV, it is possibly due to the recrystallization by the heating substrate temperatures.. Also the extinction coefficient, refractive index and dielectric constant have been studied.

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Effect of Substrate Temperature on Structural and Optical Properties of CdO Thin Films

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.27.47 ◽

2014 ◽

Vol 27 ◽

pp. 47-55

Author(s):

Hanan R.A. Ali

Keyword(s):

Thin Films ◽

Surface Roughness ◽

Optical Properties ◽

Substrate Temperature ◽

Energy Gap ◽

Spray Pyrolysis Technique ◽

Xrd Analysis ◽

Structural And Optical Properties ◽

Optical Energy Gap ◽

Cdo Thin Films

Thin films of CdO have been prepared by spray pyrolysis technique. XRD analysis reveals that all the prepared samples were polycrystalline and have preferred orientation along [111] orientation. The surface topography was determined by AFM which indicate that surface roughness and rms roughness were increased by the increasing of substrate temperature. The optical energy gap were determined and its value lies between (2.4-2.5) eV.

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Study of substrate temperature and copper doping effects on structural, electrical and optical properties of Cu-doped and undoped ZnO thin films

Journal of Materials Science Materials in Electronics ◽

10.1007/s10854-016-4771-3 ◽

2016 ◽

Vol 27 (8) ◽

pp. 7822-7828 ◽

Cited By ~ 7

Author(s):

Peipei Zhou ◽

Haonan Liu ◽

Linao Zhang ◽

Xiaoxia Suo ◽

Zhongshuai Liang ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Substrate Temperature ◽

Zno Thin Films ◽

Electrical And Optical Properties ◽

Copper Doping ◽

Doping Effects

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The Effect of Substrate Temperature on the Band Transition, Cauchy Dispersion and Urbach Energy of Nanostructure CdO Thin Films

International Letters of Chemistry Physics and Astronomy ◽

10.18052/www.scipress.com/ilcpa.58.83 ◽

2015 ◽

Vol 58 ◽

pp. 83-89

Author(s):

Muneer H. Jadduaa ◽

Zainab Ali Harbi ◽

Nadir F. Habubi

Keyword(s):

Thin Films ◽

Substrate Temperature ◽

Urbach Energy ◽

Energy Gap ◽

Chemical Spray Pyrolysis ◽

Optical Parameters ◽

Optical Energy Gap ◽

Substrate Temperature Increase ◽

Band Transition ◽

Cdo Thin Films

Thin films of CdO were prepared by chemical spray pyrolysis (CSP) . The effect of different temperature substrate (300,350,400,450 and 500) °C on some optical parameters has been studied . The transmittance and the optical energy gap were increased from (2.503-2.589) eV ,on the contrary of the rest parameters such as refractive index , real and imaginary parts of dielectric constant and Urbach energy which they were decreased as the substrate temperature increase.

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The effect of substrate temperature on the microstructural, electrical and optical properties of Sn-doped indium oxide thin films

The European Physical Journal Applied Physics ◽

10.1051/epjap/2015150004 ◽

2015 ◽

Vol 70 (3) ◽

pp. 30302 ◽

Cited By ~ 11

Author(s):

Davood Raoufi ◽

Atefeh Taherniya

Keyword(s):

Thin Films ◽

Optical Properties ◽

Substrate Temperature ◽

Indium Oxide ◽

Oxide Thin Films ◽

Electrical And Optical Properties

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EFFECT OF SUBSTRATE TEMPERATURE ON THE STRUCTURAL AND OPTICAL PROPERTIES OF NiTsPc THIN FILMS

Surface Review and Letters ◽

10.1142/s0218625x19501245 ◽

2019 ◽

Vol 27 (03) ◽

pp. 1950124 ◽

Cited By ~ 1

Author(s):

MOHAMMED YARUB HANI ◽

ADDNAN H. AL-AARAJIY ◽

AHMED M. ABDUL-LETTIF

Keyword(s):

Thin Films ◽

Grain Size ◽

Optical Properties ◽

Substrate Temperature ◽

Energy Gap ◽

Chemical Spray Pyrolysis ◽

Structural And Optical Properties ◽

Absorption Bands ◽

Tauc Plot ◽

Substrate Temperatures

Nickel(II) phthalocyanine-tetrasulfonic acid tetrasodium salt (NiTsPc) thin films were deposited on glass substrates at different substrate temperatures ([Formula: see text]) by chemical spray pyrolysis (CSP) technique. The substrate temperature varied from 110∘C to 310∘C in 50∘C steps. The substrate surface temperature is the main parameter that determines the film morphology and properties of the thin films. The structural properties of the deposited NiTsPc thin films were investigated by X-ray diffraction (XRD) and from the obtained results, it was shown that depositing thin films using 210∘C as [Formula: see text] results in higher crystallinity. Atomic force microscope (AFM) was employed to obtain the surface topography and to calculate the roughness and grain size. The smoothest thin film surface was obtained when using at 160∘C, while the highest roughness was obtained at 310∘C. The optical properties were investigated by ultraviolet visible (UV-Vis) spectrophotometer and fluorescence spectrophotometer. From the absorption spectra recorded in the wavelength range 190–1100[Formula: see text]nm, two absorption bands were observed, which are known as Soret and Q-band. By observing the absorption spectrum, it can be concluded that the deposited thin films at 110∘C–310∘C have direct energy gap. From Tauc plot relation, the energy gap ([Formula: see text]) was calculated. The values of the energy gap were between 3.05 and 3.14[Formula: see text]eV. It was observed that different [Formula: see text] highly affects the structural and optical properties of the deposited thin films. The crystallinity, grain size, roughness and the optical properties were strongly affected by the different substrate temperatures.

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