Opaque, metals

Whereas ATR spectroscopy is most commonly applied in obtaining infrared absorption spectra of opaque materials, reflection-absorption infrared spectroscopy (RAIRS) is usually used to obtain the absorption spectrum of a thin layer of material adsorbed on an opaque metal surface. An example would be carbon monoxide adsorbed on copper. The metal surface may be either in the form of a film or, of greaf imporfance in fhe sfudy of cafalysfs, one of fhe parficular crysfal faces of fhe mefal. 

The structure discussed above in EP-A-0024970 is further improved in US-A-4665609 in which an anodic oxide is applied on the surface of the detector before an opaque metal film is formed at regions surrounding the photodiodes. This anodic oxide stabilizes the pn-junctions. 

Optical absorption spectroscopy No intervalence transitions in visible region One mixed-valence transition in visible region absorption bands intensify at elevated pressures and low temperatures One or more mixed-valence transitions in visible region temperature lowers intensity of absorption bands, pressure intensifies Opaque metallic reflectivity in visible region... 

The defects existing prior to oxide CMP are usually visible through the transparent oxide film before CMP. Unlike metal CMP process, these defects cannot hide under an opaque metal film. The defects existing before oxide CMP may include... 

Jones and Ray used a modification (capillarimeter) of Ramsay and Shields s apparatus in.Avhich the different liquids are brought to the same height in the enclosed capillary by adding them to the outer vessel, and the weights of the liquids added are found. The method is comparative. The rise of mercury in (opaque) metal tubes can be investigated by X-rays. ... 

Among the simple, classical methods of determining surface or interfacial tensions is the capillary rise (or depression). It requires the use of a tube made of a material, which is not wetted either by the melt or by the metal, and, of course, to measure somehow the position of the interface, which has to be observed. The latter is difficult with opaque tubes and when the interface is below the surface of an opaque metal. Therefore, the relative movement of the liquid when the position of the tube is changed is transmitted to another liquid in a glass tube outside the furnace by means of a gas buffer. 

In LEDs with thin top confinement layers, the current is injected into the active region mostly under the top electrode. Thus, light is generated under an opaque metal electrode, which results in a low extraction efficiency. The problem can be avoided with a current-spreading layer or window layer that spreads the current under the top electrode to regions not covered by the opaque top electrode. 

Analcite partially exchanged with Ag+ underwent a photosensitized redox reaction believed to involve Ag+ with H20 within the cavities, and giving rise to Ag°. The phenomenon was manifested first by the appearance of a yellow discoloration of the bulk material, suggesting the presence of color centers, and later by opaque metallic silver disseminated along grain boundaries within analcite crystallites. 

Figure 26a shows the spectral reflectance measured at normal incidence of light of some typical evaporated opaque metal films which are used in various optical applications. 

Spectral reflectance of various opaque metal films obtained at nearly normal incidence of the light beam. The films were deposited by evaporation in high vacuum, (according to Carl Zeiss, FRG). 

Spectral reflectance of opaque metal films at 45° duced and measured by Carl Zeiss, FRG). 

One of the crucial properties is the ability to resist the chemical and electrochemical impact of the liquid crystal material. Because of electrolytic processes, the use of dc fields is generally more critical than that of ac fields. In the passive case, normally opaque metal coatings are used as a second electrode. Here similar problems occur especially in the dc case. 

OPAQUE METALS (Auto Bumper, Brass Doorplate) SPBCUUfl COLOR BY SPECULAR reflection Analyzed by Color Scal, Specular Gloss, Distir)clriesS Of>iinage Gloss, Luster, Directionality, or Surface Texture HAZE BY DIFFUSE REFLECTION Analyzed by Rtflaction Haze... 

The pigment flakes can typically be manufactured sequentially in a series of specialized roll-coating machines. In the first machine a carrier film, the sorelease layer, is deposited on a moving polymer web (transfer foil). This release layer is soluble in organic solvents so that the later formed multilayer film can be removed from the web at the end of the process. After depositing this release layer, the transfer foil is placed in a vacuum deposition roll coater and the first metal layer (e.g., chromium) as the semitransparent absorber metal is deposited followed by the first dielectric layer (e.g., magnesium fluoride) and the opaque metal layer (e.g., chromium). The second dielectric layer and the second semitransparent absorber... 

Among subwavelength plasmonic crystals described within the context of infrared photodetection, an important position belongs to 2D arrays of nanoapertures in opaque metal films. Such structures first drew attention for their abUily to transmit light in spite of the dimensions of nanoapertures that are much smaller than the operating wavelength. This effect was denoted as extraordinary optical transmission (EOT) [309]. 

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