Light induced changes in the density of states of a-Si:H

Özdemir, S.
Öktü, Özcan
Thermally stimulated conductivity (TSC) and photoconductivity were measured before and after light irradiation in hydrogenated amorphous silicon (a-Si:H) films prepared by glow discharge technique. It was observed that even medium-level of exposure to light decreased both the TSC and photoconductivity by nearly an order of magnitude over a temperature range between ∼ 100 and 300 K. From these measurements the density of gap states (DOS) between the dark Fermi level and conduction band mobility edge were calculated for the samples before and after light irradiation and the DOS was found to increase with light exposure at 105 K
Journal of Non-Crystalline Solids


ERKOC, S; Katırcıoğlu, Şenay (Elsevier BV, 1989-01-01)
The local density-of-states calculation has been carried out for the amorphous silicon thin film generated by molecular-dynamics simulation by melting and quenching process. It is found that thin amorphous silicon film has a metallic phase on the free surface region.
Determination of the influence of TiO2 on the elastic properties of a mica based glass ceramic by ultrasonic velocity measurements
Gür, Cemil Hakan; Öztürk, Abdullah (Elsevier BV, 2005-11-15)
The influence of small amount (1 or 2 wt%) of TiO2 additions and crystallization heat treatment on the elastic properties of a mica based glass ceramic have been investigated by ultrasonic velocity measurements. The mica based glass ceramic was prepared through controlled crystallization of a glass in the SiO2, Al2O3, CaO, MgO, K2O and F system. Evidences of TiO2 acting as a nucleating agent in this system was demonstrated. The longitudinal and transversal wave velocities of the as-prepared glass and the mi...
XPS study of pulsed Nd : YAG laser oxidized Si
Aygun, G.; Atanassova, E.; Kostov, K.; Turan, Raşit (Elsevier BV, 2006-08-15)
X-ray photoelectron spectra (XPS) of thin SiO2 layers grown by pulsed Nd:YAG laser at a substrate temperature of 748 K are presented, The peak decomposition technique combined with depth profiling is employed to identify the composition and chemical states of the film structure. It is established that the oxide is non-stoichiometric, and contains all oxidation states of Si in different amounts throughout the film. The interface Si/laser-grown oxide is not abrupt, and the coexistence of Si2O3 and Si2O suboxi...
Large area uniformity of plasma grown hydrogenated nanocrystalline silicon and its application in TFTs
Anutgan, Tamila Aliyeva; Anutgan, Mustafa; Atilgan, Ismail; Katircioglu, Bayram (Elsevier BV, 2010-05-15)
This work investigates the effect of RF power density (100-444 mW/cm(2)) on the structural, optical and electrical properties of the hydrogenated nanocrystalline silicon (nc-Si:H) thin films grown by plasma enhanced chemical vapor deposition (PECVD) technique. Moreover, RF power effect on the large area uniformity was analyzed by comparing the properties of the films deposited at the center and near the edge of the PECVD electrode. Film characterization was performed by Fourier transform infrared and UV-vis...
Frequency effect on electrical and dielectric characteristics of HfO2-interlayered Si-based Schottky barrier diode
Gullu, H. H.; Yildiz, D. E.; Surucu, O.; Parlak, Mehmet (Springer Science and Business Media LLC, 2020-06-01)
This study reveals the electrical properties of In/HfO2/n-Si structure with atomic layer-deposited interfacial oxide layer, HfO2 thin film between In top metal contact and monocrystalline Si wafer substrate. From the dark current-voltage measurements, the diode structure showed good rectifying behavior and low saturation current of about two order of magnitude and 1.2 x 10(- 9) A, respectively. According to the conventional thermionic emission model, zero-bias barrier height and ideality factor were calcula...
Citation Formats
S. Özdemir and Ö. Öktü, “Light induced changes in the density of states of a-Si:H,” Journal of Non-Crystalline Solids, pp. 289–294, 1989, Accessed: 00, 2020. [Online]. Available: