Oxidation of Si surface by a pulsed Nd : YAG laser

2004-06-07
Aygun, G
Atanassova, E
Alacakir, A
Ozyuzer, L
Turan, Raşit
SiO2 thin films have been obtained by 1064 nm Nd:YAG laser oxidation of p-Si in the presence of O-2. The thickness uniformity, dielectric and electrical properties of the layers have been studied. The effect of both the laser beam energy density and the substrate temperature on the oxide growth is also discussed. It was established that there exists an interval of laser beam energy density in which the oxidation occurs without surface melting. The oxidation process is controlled by the laser beam energy density rather than by the substrate temperature (673-748 K) and the higher laser power results in a thicker oxide. X-ray photoelectron spectroscopy (XPS) was used to provide information on the oxide composition. XPS results revealed that the as-grown oxide is a mixed layer of SiO2 and Si2O, which are distributed nonuniformly through the depth. MOS capacitors fabricated on the grown oxide exhibited typical capacitance-voltage, conductance-voltage characteristics. However, the density of interface states and oxide charge density were found to be higher than the typical values of thermally grown oxides. The quality of the oxide layers can be further improved by optimization of the process parameters and/or by post-processing of the grown films. It is concluded that the SiO2 films formed by the technique of Nd: YAG laser-enhanced oxidation at low temperature are potentially useful for device applications.
JOURNAL OF PHYSICS D-APPLIED PHYSICS

Suggestions

Experimental research on in-tube condensation under steady-state and transient conditions
Tanrikut, A; Yesin, O (2005-01-01)
In this research study, in-tube condensation in the presence of air was investigated experimentally at a heat exchanger of countercurrent type for different operating conditions. The test matrix for the steady-state condition covers the range of pressures P = 1.8 to 5.5 bars, vapor Reynolds numbers Re, = 45 000 to 94 000, and inlet air mass fraction values Xi = 0 to 52%. The effect of air manifests itself by a reduction in the local heat flux and the local heat transfer coefficient. The local heat transfer ...
Adsorption calorimetry in supported catalyst characterization : adsorption structure sensitivity on pt(y-Al2o3
Üner, Murat; Üner, Deniz; Department of Chemical Engineering (2004)
In this study, the structure sensitivity of hydrogen, oxygen and carbon monoxide adsorption was investigated by changing the metal particle size of Pt/Al2O3 catalysts. 2 % Pt/Al2O3 catalysts were prepared by incipient wetness method; the particle size of the catalysts was manipulated by calcining at different temperatures. The dispersion values for the catalysts calcined in air at 683K, 773K and 823K were measured as 0.62, 0.20 and 0.03 respectively. The differential heats of adsorption of hydrogen, carbon ...
Determination of trace elements in marine plankton by inductively coupled plasma mass spectrometry (ICP-MS)
Arslan, Z; Ertas, N; Tyson, JF; Uden, PC; Denoyer, ER (Springer Science and Business Media LLC, 2000-02-01)
A method has been developed for the determination of 23 elements in marine plankton in which inductively coupled plasma (ICP) source mass spectrometry (MS) was used to quantify the elements in the solution after digestion in a mixture of hydrofluoric and nitric acids in sealed PTFE vessels in a microwave field. The procedure was validated by the analysis of a standard reference soil (SRM 2709 San Joaquin Soil) and a standard reference fresh water plankton (CRM 414). The method was applied to the analysis of...
Numerical investigation of self-organization and stable burning conditions of moderate pressure glow discharges in argon gas
Eylenceoğlu, Ender; Rafatov, İsmail; Department of Physics (2011)
In this study numerical modelling of a moderate pressure DC glow discharge plasma is car- ried out in 1D and 2D geometry. The governing equations include continuity equations for the plasma species (electrons, positive ions and metastable atoms), the electron energy equation (EEE), Poisson equation for the electric field in the discharge volume and the surface charge equation on the dielectric side walls. The electron transport coefficients such as the electron diffusion and mobility as well as the electron-imp...
Antioxidant enzyme activities in rat liver tissues of diabetic rats
Sadi, Gökhan; Güray, Tülin; Department of Biochemistry (2004)
Free radicals are the compounds having one or more unpaired electrons in their outer orbital and this unpaired electron make these compounds very reactive. Especially as their concentration increases, they initiate a chain oxidation reaction of lipids, proteins and nucleic acids. The condition, in which the production of free radicals exceeds their elimination or tissue defense mechanism decrease against them or both occur together, is called oxidative stress. In diabetes mellitus which is a glucose metabol...
Citation Formats
G. Aygun, E. Atanassova, A. Alacakir, L. Ozyuzer, and R. Turan, “Oxidation of Si surface by a pulsed Nd : YAG laser,” JOURNAL OF PHYSICS D-APPLIED PHYSICS, pp. 1569–1575, 2004, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/39981.