Preparation and Characterization of N-CdS Thin Films and its Schottky Barrier

2013 ◽  
Vol 665 ◽  
pp. 307-310
Author(s):  
K.D. Patel ◽  
Keyur S. Hingarajiya ◽  
Mayur M. Patel ◽  
V.M. Pathak ◽  
R. Srivastava
Keyword(s):  
Thin Films ◽  
Barrier Height ◽  
Thermionic Emission ◽  
Cadmium Sulphide ◽  
Optical Characterization ◽  
Point Of View ◽  
Flat Band ◽  
Zero Bias ◽  
Cds Thin Films

Cadmium sulphide (CdS), a member of group II-VI semiconductors is one of the promising materials from its applications point of view. The present investigations are about the preparation, structural and optical characterization of CdS thin films and their use as Schottky diode with Aluminum. Thin films of CdS having thickness around 700nm have been deposited by thermal evaporation. The chemical composition of the deposited CdS thin films has been made using EDAX technique. The structural characterization of this films was carried out using XRD. The structure of CdS after the deposition was found to be Cubic. Also, the lattice parameters were evaluated from the XRD data. From TEM of CdS thin films, the polycrystalline nature was confirmed. Optical characterization has been carried out using UV-VIS-IR spectroscopy. The direct as well as indirect band gaps obtained are 1.64eV and 1.48eV respectively. Schottky junctions were formed by a thermal vapor-deposition of 500nm Al films on pre-coated CdS glass substrates. Diode parameters, such as the zero bias barrier height φb0, the flat band barrier height φbf and the ideality factorη, were calculated using thermionic emission theory at room temperature.

Investigation of carrier transport mechanisms in the Cu–Zn–Se based hetero-structure grown by sputtering technique

2018 ◽  
Vol 96 (7) ◽  
pp. 816-825 ◽  
Author(s):  
H.H. Güllü ◽  
M. Terlemezoğlu ◽  
Ö. Bayraklı ◽  
D.E. Yıldız ◽  
M. Parlak
Keyword(s):  
Barrier Height ◽  
Carrier Transport ◽  
Thermionic Emission ◽  
Electrical Characterization ◽  
Band Gap Energy ◽  
Zero Bias ◽  
Hetero Structure ◽  
Current Voltage ◽  
P Type

In this paper, we present results of the electrical characterization of n-Si/p-Cu–Zn–Se hetero-structure. Sputtered film was found in Se-rich behavior with tetragonal polycrystalline nature along with (112) preferred orientation. The band gap energy for direct optical transitions was obtained as 2.65 eV. The results of the conductivity measurements indicated p-type behavior and carrier transport mechanism was modelled according to thermionic emission theory. Detailed electrical characterization of this structure was carried out with the help of temperature-dependent current–voltage measurements in the temperature range of 220–360 K, room temperature, and frequency-dependent capacitance–voltage and conductance-voltage measurements. The anomaly in current–voltage characteristics was related to barrier height inhomogeneity at the interface and modified by the assumption of Gaussian distribution of barrier height, in which mean barrier height and standard deviation at zero bias were found as 2.11 and 0.24 eV, respectively. Moreover, Richardson constant value was determined as 141.95 Acm−2K−2 by means of modified Richardson plot.

Electrical Characterization of In Schottky Contacts to Epitaxial n-In0.46Ga0.54P Grown on n+-GaAs by Mocvd

1996 ◽  
Vol 448 ◽  
Author(s):  
N. Marcano ◽  
A. Singh
Keyword(s):  
Barrier Height ◽  
Thermionic Emission ◽  
Electrical Characterization ◽  
Interface Layer ◽  
Zero Bias ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Direct Current Voltage ◽  
Etched Surface

AbstractIn/n-In0.46Ga0.54P Schottky diode was fabricated by thermal evaporation of In on chemically etched surface of In0.45Ga0.54P:Si epitaxial layer grown on highly doped n type GaAs. The In metal formed a high quality rectifying contact to In0.46Ga0.54P:Si with a rectification ratio of 500. The direct current-voltage/temperature (I-V/T) characteristics were non-ideal with the values of the ideality factor (n) between 1.26-1.78 for 400>T>260 K. The forward I-V data strongly indicated that the current was controlled by the generation-recombination (GR) and thermionic emission (TE) mechanisms for temperature in the range 260-400 K. From the temperature variation of the TE reverse saturation current, the values of (0.75±0.05)V and the (4.5±0.5)×10-5 Acm-2K-2 for the zero bias zero temperature barrier height (φoo) and modified effective Richardson constant were obtained. The 1 MHz capacitance-voltage (C-V) data for 260 K < T < 400 K was analyzed in terms of the C-2-V relation including the effect of interface layer to obtain more realistic values of the barrier height (φbo). The temperature dependence of φbo was described the relation φbo =(0.86±10.03) - (8.4±0.7)×l0-4T. The values of φoo, obtained by the I-V and C-V techniques agreed well.

scholarly journals Approximate methods for the optical characterization of inhomogeneous thin films: Applications to silicon nitride films

2019 ◽  
Vol 70 (7) ◽  
pp. 16-26
Author(s):  
Ivan Ohlídal ◽  
Jiří Vohánka ◽  
Daniel Franta ◽  
Martin Čermák ◽  
Jaroslav Ženíšek ◽  
...  
Keyword(s):  
Thin Films ◽  
Silicon Nitride ◽  
Optical Characterization ◽  
Point Of View ◽  
Approximate Methods ◽  
Multilayer Systems ◽  
Practical Point ◽  
Advantages And Disadvantages ◽  
Silicon Nitride Films

Abstract In this paper the overview of the most important approximate methods for the optical characterization of inhomogeneous thin films is presented. The following approximate methods are introduced: Wentzel–Kramers–Brillouin–Jeffreys approximation, method based on substituting inhomogeneous thin films by multilayer systems, method based on modifying recursive approach and method utilizing multiple-beam interference model. Principles and mathematical formulations of these methods are described. A comparison of these methods is carried out from the practical point of view, ie advantages and disadvantages of individual methods are discussed. Examples of the optical characterization of three inhomogeneous thin films consisting of non-stoichiometric silicon nitride are introduced in order to illustrate efficiency and practical meaning of the presented approximate methods.

The Synthesis and Characterization of Novel Cadmium Sulphide Nanocrystallites and their Thin Films

2014 ◽  
Vol 875-877 ◽  
pp. 228-231
Author(s):  
Shafique Ahmed Arain ◽  
Christopher Wilkins ◽  
Hafiz Badaruddin
Keyword(s):  
Thin Films ◽  
Vapour Deposition ◽  
Hexagonal Phase ◽  
Chemical Vapour ◽  
Cadmium Sulphide ◽  
Spherical Shape ◽  
Sem Analysis ◽  
Diethyl Dithiocarbamate ◽  
Lower Temperature

Diethyl dithiocarbamate [Cd (S2CN Et2)2] complex is used to deposit the cadmium sulphide thin film at much lower temperature by Aerosol Assisted Chemical Vapour deposition (AACVD) and same precursor is used to synthesize the nanocrystals in Oleylamine at elevated temperature. Thermogravimetric analysis shows that precursor [Cd (S2CN Et2)2] decomposes in the single stage, losing 62% of total weight. Deposition of thin films at 300°C and 400°C showed the growth of CdS clusters which were made of granular crystallites. These results are confirmed by SEM analysis. Thermolysis of the precursor in oleylamine at 240°C gave the nanoparticles most of them are monodispersed spherical shape, few having mono and dipod structures. TEM images confirm the structures. XRD results show the thin films and nanoparticles have hexagonal phase of CdS.

Structural and Optical Characterization of Zinc Telluride Thin Films

2013 ◽  
Vol 665 ◽  
pp. 254-262 ◽  
Author(s):  
J.R. Rathod ◽  
Haresh S. Patel ◽  
K.D. Patel ◽  
V.M. Pathak
Keyword(s):  
Thin Films ◽  
Extinction Coefficient ◽  
Nir Spectroscopy ◽  
Optical Characterization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Evaporation Technique ◽  
Film Form ◽  
Znte Thin Films

Group II-VI compounds have been investigated largely in last two decades due to their interesting optoelectronic properties. ZnTe, a member of this family, possesses a bandgap around 2.26eV. This material is now a day investigated in thin film form due to its potential towards various viable applications. In this paper, the authors report their investigations on the preparation of ZnTe thin films using vacuum evaporation technique and their structural and optical characterizations. The structural characterization, carried out using an X-ray diffraction (XRD) technique shows that ZnTe used in present case possesses a cubic structure. Using the same data, the micro strain and dislocation density were evaluated and found to be around 1.465×10-3lines-m2and 1.639×1015lines/m2respecctively. The optical characterization carried out in UV-VIS-NIR region reveals the fact that band gap of ZnTe is around 2.2eV in present case. In addition to this, it was observed that the value of bandgap decreases as the thickness of films increases. The direct transitions of the carries are involved in ZnTe. Using the data of UV-VIS-NIR spectroscopy, the transmission coefficient and extinction coefficient were also calculated for ZnTe thin films. Besides, the variation of extinction coefficient with wavelength has also been discussed here.

Simulation and prediction of optical characterization of casting (Adamantan-Fulgide) thin films using (CTANNs) approach

2019 ◽  
Vol 33 (11) ◽  
pp. 1950093 ◽  
Author(s):  
A. M. A. EL-Barry ◽  
D. M. Habashy
Keyword(s):  
Experimental Data ◽  
Thin Films ◽  
Back Propagation ◽  
Optical Characterization ◽  
Experimental Information ◽  
Training Algorithm ◽  
Energy Gaps ◽  
Resilient Back Propagation ◽  
Good Agreement

For reinforcement, the photochromic field and the cooperation between the theoretical and experimental branches of physics, the computational, theoretical artificial neural networks (CTANNs) and the resilient back propagation (R[Formula: see text]) training algorithm were used to model optical characterizations of casting (Admantan-Fulgide) thin films with different concentrations. The simulated values of ANN are in good agreement with the experimental data. The model was also used to predict values, which were not included in the training. The high precision of the model has been constructed. Moreover, the concentration dependence of both the energy gaps and Urbach’s tail were, also tested. The capability of the technique to simulate the experimental information with best accuracy and the foretelling of some concentrations which is not involved in the experimental data recommends it to dominate the modeling technique in casting (Admantan-Fulgide) thin films.

Optical characterization of thin films by guided waves

1989 ◽  
Vol 28 (14) ◽  
pp. 2918 ◽  
Author(s):  
Emile Pelletier ◽  
F. Flory ◽  
Y. Hu
Keyword(s):  
Thin Films ◽  
Guided Waves ◽  
Optical Characterization
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