The optical and structural properties for 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) films deposited on Au-coated substrates at the various growth temperatures by the organic molecular beam deposition (OMBD) method have been studied. The planar PTCDA molecules were oriented almost parallel to the substrate surface in the films deposited at the growth temperature of -160° C. Orientational disorder of the molecular planes occurred especially in the films grown at higher substrate temperatures. These films had basically large anisotropy of refractive indices which were evaluated by the prism attenuated total-reflection (ATR) method. The anisotropy of indices decreased for the film grown at the substrate temperature of 100° C. The optical anisotropy has been understood in terms of the molecular orientation.

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Silicon dioxide (SiO2) films formed by chemical vapor deposition (CVD) were treated with oxygen radical oxidation using Ar/O2 plasma excited by microwave. The mass density depth profiles, carrier trap densities, and current-voltage characteristics of the radical-oxidized CVD-SiO2 films were investigated. The mass density depth profiles were estimated with x ray reflectivity measurement using synchrotron radiation of SPring-8. The carrier trap densities were estimated with x ray photoelectron spectroscopy time-dependent measurement. The mass densities of the radical-oxidized CVD-SiO2 films were increased near the SiO2 surface. The densities of the carrier trap centers in these films were decreased. The leakage currents of the metal-oxide-semiconductor capacitors fabricated by using these films were reduced. It is probable that the insulation properties of the CVD-SiO2 film are improved by the increase in the mass density and the decrease in the carrier trap density caused by the restoration of the Si-O network with the radical oxidation.

Flow accelerated corrosion (FAC) is divided into two processes: a corrosion (chemical) process and a flow dynamics (physical) process. The former is the essential process to cause FAC and the latter is the accelerating process to enhance FAC occurrence. The chemical process in the surface boundary layer is analyzed to evaluate FAC rate. Contributions of flow dynamics on wall thinning rate due to FAC are expressed as a function of mass transfer coefficient but not that of flow velocity. FAC evaluation procedures were divided into 5 steps as follows. (1) Flow pattern and temperature in each elemental volume along the flow path were obtained with 1D computational flow dynamics (CFD) codes, (2) corrosive conditions, e.g., oxygen concentration and electrochemical corrosion potential (ECP) along the flow path were calculated with a hydrazine oxygen reaction code, (3) precise flow patterns and mass transfer coefficients at the structure surface were calculated with 3D CFD codes, (4) danger zones were evaluated by coupling major FAC parameters, and then, (5) wall thinning rates were calculated with the coupled model of static electrochemical analysis and dynamic double oxide layer analysis at the identified danger zone. Anodic and cathodic current densities and ECPs were calculated with the static electrochemistry model and ferrous ion release rate determined by the anodic current density was used as input for the dynamic double oxide layer model. Thickness of the oxide film and its characteristics determined by the dynamic double oxide layer model were used for the electrochemistry model to determine the resistances of cathodic current from the bulk to the surface and anodic current from the surface to the bulk. Two models were coupled to determine local corrosion rate and ECP for various corrosive conditions. The calculated results of the coupled models had good agreement with the measured ones.

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