Passivity properties

More effort has probably been devoted to study of the corrosion and passivation properties of Fe-Cr-Ni alloys, e.g. stainless steel and other transition-metal alloys, than to any other metallic system [2.42, 2.44, 2.55, 2.56]. The type of spectral information obtainable from an Fe-Cr alloy of technical origin, carrying an oxide and contaminant film after corrosion, is shown schematically in Fig. 2.13 [2.57]. 

The high potential of the positive electrode, on the other hand, does not allow the use of conducting metals like copper within the positive electrode. Lead can be used instead due to its passive properties caused by a (PbO 2) layer that largely protects the underlying material, but conducts the electronic current and so allows electrochemical reactions at its surface. 

The corrosion of stainless steel in 0.1 mol-1 NaCl solutions at open circuit potential was studied in detail by Bruesch et al. [106] using XPS in combination with a controlled sample transfer system [38]. It was verified by XPS analysis that the passivating film contains chromium oxide. The position and the height of the Cr concentration maximum depends critically on the bulk chromium content of the steel. Significant variations in the electrode passivation properties were observed at a Cr concentration of 12%, while the film behaviour was found to be rather independent of the other components like Mo, Ni, Cu. From the fact that the film structures and... 

The present work is a report of the properties of polyimide which define functionality as an interlevel dielectric/passivant. Thus, the planarizing and patterning characteristics and electrical characteristics of current vs voltage, dissipation, breakdown field strength, dielectric constant, charge and crossover isolation are discussed in addition to the reliability-related passivation properties. 

Insulation Integrity. Insulation integrity is a function of an interlayer dielectric/passivant defined by specific electrical, mechanical and passivation properties. The D.C. electrical property of interest is the I-V characteristic which is used to deduce conductivity and breakdown field strength. The corresponding A.C. electrical property is dissipation factor. The pertinent mechanical and passivation properties are, respectively, pinhole density and performance rating as a diffusion barrier to Na" " and H2O. 

Finally, the passivation properties of polyimide are superior to phosphoslllcate glass under conditions of severe PTHB testing. 

The success of CD CdS in photovoltaic cells has driven related research with potential applications in other semiconductor devices. Since the CD process seems to play a role in the favorable properties of the CdS windows by decreasing interface recombination, studies of its passivation properties on other interfaces and surfaces have been carried out, with considerable success. For example, when a very thin film (ca. 6 nm) was deposited between InP and SiOi, the resulting reduction of the interface state density led to improved electrical properties of metal-insulator-semiconductor capacitors and field effect transistors (FETs)... 

Weidmann S Passive properties of cardiac fibers in Rosen MR, Janse MJ, Wit AL (eds) Cardiac Electrophysiology. A Textbook. Mount Klsco, Futura, 1990, pp 29-35. 

We should also distinguish between active and passive properties. An active property emits or sends out some sort of information-carrying energy that is intrinsic to the object s nature. My desk lamp has an active property it emits light waves. If an object has passive properties, it does not emit such energy. This book is passive. If no light impinges on it from the outside to be reflected back, you will not be able to see it. 

Under -> open-circuit conditions a possible passivation depends seriously on the environment, i.e., the pH of the solution and the potential of the redox system which is present within the electrolyte and its kinetics. For electrochemical studies redox systems are replaced by a -> potentiostat. Thus one may study the passivating properties of the metal independently of the thermodynamic or kinetic properties of the redox system. However, if a metal is passivated in a solution at open-circuit conditions the cathodic current density of the redox system has to exceed the maximum anodic dissolution current density of the metal to shift the electrode potential into the passive range (Fig. 1 of the next entry (- passivation potential)). In the case of iron, concentrated nitric acid will passivate the metal surface whereas diluted nitric acid does not passivate. However, diluted nitric acid may sustain passivity if the metal has been passivated before by other means. Thus redox systems may induce or only maintain passivity depending on their electrode potential and the kinetics of their reduction. In consequence, it depends on the characteristics of metal disso-... 

Some of what we see as the principal properties and characteristics of import in the development and selection of viscoelastic materials for structural damping are listed below. Table IV notes "passive" properties and characteristics, that is, those that pertain to the material itself and to its performance in the specified operating conditions. Somewhat in contrast. Table V lists "Active or Interactive" properties and characteristics that concern the interaction of the viscoelastic material with other materials and with the environment of the treatment. These tabulations are surely incomplete, but are intended to suggest the breadth of considerations that may be involved in material selection. 

Table IV. Viscoelastic Materials for Damping. Passive Properties and Characteristics...

What is the effect of temperature on the passivating property of a corrosion inhibitor during CMP process ... 

Another way to stabilize the HTSC surface state is to passivate it by the formation of thin, compact, chemically inactive films. Chemical methods of passivation in solution [521] generally consist in the formation of poorly soluble salts (sulfides, iodides, oxalates, etc.) of the metal components. The oxidation of the thin surface layers accepted for the passivation of semiconductors [220,221] apparently cannot be directly applied for oxide materials, and requires further development. The insoluble compounds that form on HTSC surfaces do not display pronounced passivating properties. 

Stricharts( What is the evidence that the passive properties for these very small processes with large surfaceivolume ratios are changed as a result of Na accumulation, affecting for example delayed rectifier K channels or Ca2 -activated K channels In most of the modelling, you assumed that the passive properties were invariant you just added an active process on top of that. 

Strichart Have you looked for changes in passive properties that would persist after these active properties are over, but during a period when intracellular ions might still be elevated ... 

Of the layers mentioned above, the thin films showing the widest range of stress are the PECVD oxides. The stress state of the oxide layers becomes important when such films are used as part of a membrane or as a passivation layer. Membranes that are under considerable compressive stress tend to buckle, severely changing their mechanical properties. In contrast, considerable tensile stress in membranes can lead to crack formation and fracture. The passivation properties of PECVD oxide layers, for example, towards humidity, depend sensitively on their composition, which, in turn, has a great influence on the stress. 

The growth of silicon oxide (silica) on the surface of elemental silicon under ambient conditions, and the superior passivation properties of the resulting oxide/silicon interface, have prompted the extensive investigations on CVD of Si02 (Sect. 5.4.1). However, the drawbacks of Si02 in turn have induced investigations into other dielectric... 

AlMe, N20 N2 LPCVD 950-1050 70 good passivation properties of Si MOS devices [89,90]... 

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