Coatings ultra-thin

Limited solubility in selected perfluorinated solvents (unique amongst commercial fluoropolymers), enabling solution-cast ultra-thin coatings in the submicrometre thickness range. 

Another good example of the effects of aerogel nanostructure on the electrochemical behavior of materials is shown in the electroactive behavior of Mn02. As micrometer-thick films or deposits, Mn02 has exhibited a specific capacitance of 150 to 250 F/g (42-44). When synthesized as a nanoscale, ultra-thin coating, Mn02 can deliver a specific capacitance of over 700 F/g (45-47). In a study by Fischer et al. (48), a... 

Ellipsometry in the vacuum UV (< 190 nm) enables the analysis of materials for the next generation lithography (photoresist, AR coatings) at the latest exposure wavelengths (157 nm and 193 nm). The short wavelengths increase the sensitivity of ellipsometric measurements of ultra thin films (<10 nm). New prospects are expected for the analysis of thin metallic and dielectric layers. 

Ultra-thin DLC Coatings in Magnetic Disk Driver... 

Sundararajan, S., and Bhushan, B., Micro/Nanotribology of Ultra-thin Hard Amorphous Carbon Coatings Using Atomic Force/Friction Force Microscopy," Wear, Vol. 225-229, 1999, pp. 678-689. 

Bhushan, B., Chemical, Mechanical and Tribological Characterization of Ultra-Thin and Hard Amorphous Carbon Coatings as thin as 3.5 nm Recent Developments," Diamond Relat. Mater., Vol. 8,1999,pp. 1985-2015. 

The biggest challenge to produce an ultra-thin (about 1 nm) overcoat is to make the coating free of pin-holes while maintaining the durability and tribological properties. In an HDD system, pin-holes can cause much more contaminants from all sources, such as outgas compounds from polymeric foam components, pressure sensitive adhesives, ionic residues from improperly cleaned components and ambient pollutants, which can be detrimental to the tribology and durability of the HDD. Therefore, efforts have been made mainly on the improvement of carbon film [4-7]. 

Han, H., Ryan, R, and McClure, M., Ultra-thin Tetrahedral Amorphous Carbon Eilm as Solider Overcoat for High Areal Density Magnetic Recording," Surface and Coatings Technology,Vol. 121,1999,pp. 579-584. 

The gold-coated outer surface is protected by an ultra thin window of polymer which has been coated with evaporated metal in order to minimise light transmission. 

Joel, V. Monzon Hernandez, D., Fast detection of hydrogen with nano fiber tapers coated with ultra thin palladium layers, Opt. Express 2005, 13, 5087 5092... 

Fig. 13.10a. An MNF was coated with an ultra thin palladium film. The operational principle of this sensor was based on the fact that a thin palladium film has the ability to selectively absorb hydrogen. If a palladium film is exposed to hydrogen, its refractive index, and, in particular, absorbance, changes. The change in refractive index causes a change in transmission power of an MNF. The MNF fabricated in Ref. 15 had a palladium film of 4 nm in thickness and 2 mm in length. In Fig. 13.10b, the transmission power of the MNF is shown as a function of time when the sensor was exposed successively to a 3.9% concentration of hydrogen. The response time calculated from the plot was 10 s. This response time is 3 5 times faster than that of other optical hydrogen sensors and about 15 times faster than that of some electrical nano hydrogen sensors. The fast response of the sensor is, presumably, due to the ultra small thickness of the palladium film that is rapidly filled with hydrogen. Figure 13.10c shows the transmission of this sensor as a function of time for...

Plasma surface treatment of many polymers, including fabrics, plastics, and composites, often occurs. The production of ultra-thin films via plasma deposition is important in microelectronics, biomaterials, corrosion protection, permeation control, and for adhesion control. Plasma coatings are often on the order of 1 100 nm thick. 

Metal reflector plate based pigments. Metal reflector based systems, developed by DuPont, Flex Products and BASF," consist of a metal disc, usually aluminium, coated with a dielectric layer, such as SiOj or MgF, followed by an ultra-thin transparent layer or an absorbing layer, e.g. FejOj. Some of the possible combinations are shown in Figure 5.20. 

Developments in modern CVD allow to improve the deposition of thin films and bulky coatings nevertheless, an additional major issue remains the building of nanostructured materials such as ultra-thin films or dispersed nanoparticles. For these applications, the control of the deposit at the atomic or nano-scale level is essential. Consequently, the role of surface chemistry occurring between the CVD precursor and the substrate, as well as the gas-phase main physical properties have to be indisputably clarified. 

It is of interest primarily for very uniform ultra-thin films and coatings (0.002-5 mils) in applications such as electrical resistors, thermistors, thermocouples, stator cores, connectors, fast-sensing probes, photo cells, memory units, dropwise steam condensers for recovery of sea water, pellicles for beam splitters in optical instruments, windows for nuclear radiation counters, panels for micrometeorite detection, dielectric supports for planar capacitors, encapsulation of reactive powders, and supports in x-ray and optical work. Any significant growth would depend upon a major breakthrough in process techniques and a consequent lowering in price. 

Gao, C. Lee, Y. C. Chao, J. Russak, M. Dip-Coating of Ultra-Thin Liquid Lubricant and Its Control for Thin-Film Magnetic Hard Disks. IEEE Trans. Magn. 1995, 31, 2982-2984. 

Semiconductors are ultra-thin, polished wafers often made of pure silicon, one of the most abundant elements on Earth. One of the first steps in making a semiconductor is to use deposition to coat the surface of the wafer. Depending on the intended use for the semiconductor, it can be coated with a variety of materials. 

Si(Li) detectors without Be windows ("windowless") or with thin metal-coated polymer films (Ultra-Thin Window UTW) have become an important peripheral to modern-day AEMs for the qualitative detection of elements with 5vacuum requirements because the removal of the Be window increases the probability of detector contamination (from the specimen or column environment) and consequent degradation of performance [12]. Windowless and UTW Si(Li) detectors are commonly installed with additional airlock mechanisms and only on instruments with acceptable levels of vacuum cleanliness. Thus, design constraints on modern AEMs preclude placement of the UTW detector close to the sample. In addition, loss of detection efficiency at low energies (light-element K-lines with the L-lines of transition metals all conspire to limit windowless or UTW EDS analysis of minerals to a qualitative basis only. 

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