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...
Electrical transport mechanism in boron nitride thin film
ÖZDEMİR, Orhan; Anutgan, Mustafa; Aliyeva-Anutgan, Tamila; Atilgan, Ismail; Katircioglu, Bayram (Elsevier BV, 2009-06-01)
Both dc and ac transport characteristics of plasma enhanced chemical vapor deposited (PECVD) boron nitride (BN) thin film was investigated by dc current vs. dc voltage measurement at different temperatures and admittance vs. gate voltage at various frequencies/temperatures, respectively. MIM metal (Al)-insulator (BN)-metal (Al) or MIS metal (Al)-BN-semiconductor (p-Silicon) test devices were conventionally produced. Both conductivity anisotropy and dc/ac detailed transport mechanism were analyzed within t...
Photoluminescence spectroscopy in the study of growth of CdSxSe1-x nanocrystals in glass
Allahverdi, C; Yukselici, MH; Turan, Raşit; Seyhan, A (IOP Publishing, 2004-08-01)
Growth of CdS0.08Se0.92 nanocrystals embedded in glass is studied through the combinative analysis of optical absorption and photoluminescence (PL) spectroscopy at room temperature. The quantum confinement effect is observed in these structures. Average nanocrystal radii are found to be in the range of 2.3-4.2 nm with the help of a quantized state effective mass theory. Photoluminescence spectra are studied by means of the model of Ravindran et al (1999 Nanostruct. Mater. 11 603). The difference between the...
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: