Influence of photonic excitations on the electrical parameters of TlInS2 crystals

2010-04-01
QASRAWI, ATEF FAYEZ HASAN
Hasanlı, Nızamı
The photo-excitation effect on the current transport mechanism in TlInS2 crystals has been studied by means of dark and illuminated conductivity measurements. The temperature-dependent electrical conductivity analysis in the temperature region of 110-340 K revealed the domination of the thermionic emission and the thermally assisted variable range hopping (VRH) of charge carriers above and below 160 K, respectively. Above 160 K, the conductivity activation energies in the dark are found to be 0.28 and 0.15 eV in the temperature regions of 340-240 K and 230-160 K, respectively. In the temperature region of 110-150 K, the dark variable range hopping analysis revealed a density of localized states of 1.99x 10(22) cm(-3)eV(-1), an average hopping distance of 0.53 nm and an average hopping energy of 79.65 meV. When the sample was photo-excited, the values of the conductivity activation energies, the density of localized states near the Fermi level and the average hopping energy were observed to decrease sharply with increasing illumination intensity. On the other hand, the average hopping distance increased with rising illumination intensity. Such behaviours were attributed to the Fermi level shift and/or trap density reduction by electron-hole recombination. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
CRYSTAL RESEARCH AND TECHNOLOGY

Suggestions

Influence of ion implantation on structural and photoconductive properties of Bridgman grown GaSe single crystals
KARABULUT, ORHAN; Parlak, Mehmet; Turan, Raşit; SERİNCAN, UĞUR; Akınoğlu, Bülent Gültekin (Wiley, 2006-03-01)
The structure and temperature dependent spectral photoconductivity of as-grown and N-and Si-implanted GaSe single crystals have been studied. It was observed that post-annealing results in a complete recovery of the crystalline nature that was moderately reduced upon implantation. The band edge is shifted in the implanted sample which is attributed to the structural modifications and continuous shallow levels introduced upon implantation and annealing. Our calculations showed that the trap density is increa...
Effect of temperature and isomorphic atom substitution on optical absorption edge of TlInS2xSe2(1-x) mixed crystals (0.25 <= x <= 1)
Hasanlı, Nızamı (Wiley, 2010-05-01)
The optical properties of the TlInS2xSe2(1-x) mixed crystals (0.25 <= x <= 1) have been investigated through the transmission and reflection measurements in the wavelength range of 400-1100 nm. The optical indirect band gap energies were determined by means of the analysis of the absorption data. It was found that the energy band gaps decrease with the increase of selenium atoms content in the TlInS2xSe2(1-x) mixed crystals. The transmission measurements carried out in the temperature range of 10-300 K reve...
Effect of isomorphic atom substitution on the refractive index and oscillator parameters of TlInS2xSe2(1-x) (0.25 <= x <= 1) layered mixed crystals
Hasanlı, Nızamı (Wiley, 2010-11-01)
The optical properties of TlInS2xSe2(1-x) mixed crystals (0.25 <= x <= 1) have been studied at room temperature through the transmittance and reflectivity measurements in the wavelength range of 400-1100 nm. The spectral dependence of the refractive index for all compositions of studied crystals were obtained. The dispersion of the refractive index is discussed in terms of the Wemple-DiDomenico single-effective-oscillator model. The compositional dependencies of refractive index dispersion parameters: oscil...
Effects of annealing on structural, electrical and optical properties of AgGa(Se0.5S0.5)(2) thin films deposited by using sintered stoichometric powder
KARAAĞAÇ, HAKAN; Parlak, Mehmet (Wiley, 2009-04-01)
The structural, electrical and optical properties of AgGa(Se0.5S0.5)(2) thin films deposited by using the thermal evaporation method have been investigated as a function of annealing in the temperature range of 450-600 degrees C. X-ray diffraction (X-RD) analysis showed that the structural transformation from amorphous to polycrystalline structure started at 450 degrees C with mixed binary phases of Ga2Se3, Ga2S3, ternary phase of AgGaS2 and single phase of S. The compositional analysis with the energy disp...
Analysis of the Hall effect in TlGaTe2 single crystals
QASRAWI, ATEF FAYEZ HASAN; Hasanlı, Nızamı (IOP Publishing, 2009-06-10)
The electrical resistivity and Hall coefficient of p-type TlGaTe2 crystals were measured in the temperature range of 110-320 K. The electrical resistivity, charge carrier density and Hall mobility data for the crystals have been analyzed by means of existing theories and models to determine the extrinsic energy levels, the carrier effective mass, the donor and acceptor concentrations and the dominant scattering mechanism in the crystal as well. The analysis of the temperature-dependent electrical resistivit...
Citation Formats
A. F. H. QASRAWI and N. Hasanlı, “Influence of photonic excitations on the electrical parameters of TlInS2 crystals,” CRYSTAL RESEARCH AND TECHNOLOGY, pp. 433–438, 2010, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/48867.