Coating epitaxial coatings

Beyond PVD and CVD, there are techniques from the liquid/solution phase such as sol-gel, spray coating, spin coating, electrochemical deposition and liquid phase epitaxy. The sol-gel process is the most widely used method for the deposition of metal oxide for gas sensors. 

The experiments described above are just a few examples illustrating how surface SHG can be used to probe adsorbates at various interfaces. There are undoubtedly many other possible applications one can think of. Among them, the potential use of the technique to study surface dynamics is very exciting. The possibility of using surface SHG to study coating, epitaxial growth, corrosion, and catalysis is equally fascinating. 

Atomic layer epitaxy Coating in and outside pores SnO, CoSi2, Sia-xiGcx Dueso et al. (1996), Loni (1997)... 

Recent applications of e-beam and HF-plasma SNMS have been published in the following areas aerosol particles [3.77], X-ray mirrors [3.78, 3.79], ceramics and hard coatings [3.80-3.84], glasses [3.85], interface reactions [3.86], ion implantations [3.87], molecular beam epitaxy (MBE) layers [3.88], multilayer systems [3.89], ohmic contacts [3.90], organic additives [3.91], perovskite-type and superconducting layers [3.92], steel [3.93, 3.94], surface deposition [3.95], sub-surface diffusion [3.96], sensors [3.97-3.99], soil [3.100], and thermal barrier coatings [3.101]. 

Another recently discovered form of epitaxy is graphoepitaxy (Geis et al. 1979). Here a non-crystalline substrate (often the heat-resistant polymer polyi-mide, with or without a very thin metallic coating) is scored with grooves or pyramidal depressions the crystalline film deposited on such a substrate can have a sharp texture induced by the geometrical patterns. More recently, this has been tried out as an inexpensive way (because there is no need for a monocrystalline substrate) of preparing oriented ZnS films for electroluminescent devices (Kanata et al. 1988). 

The practical result of epitaxy is a very high degree of adhesion between coating and substrate. The force needed to separate the interface is similar to that needed to break the metals on either side. Where a true metallic bond forms at an epitaxial interface it is only possible to measure adhesion if the bond is the weakest of the three near the interface. An adhesion test based on breaking the joint indicates only which of the three is weakest. For practical purposes any epitaxial joint will have a strength more than adequate for service conditions. 

Epitaxy the phenomenon whereby a deposit or coating takes up the lattice habit and orientation of the substrate. 

Chemical Vapor Deposition Electrochemical Deposition Molecular Beam Epitaxy Atomic Layer Deposition Thermal Oxidation Spin Coating... 

Substrates DME = dropping mercury electrode FTO = fluorine-doped tin oxide G = graphite GC = glassy carbon GrC = graphic carbon ITO = indium tin oxide-coated glass SC = single crystals SS = stainless steel TCO = transparent conducting oxide VC = vitrious carbon. Miscellaneous ECALE = electrochemical atomic layer epitaxy ED = electrodeposition ML = monolayer RT = room temperature SMD = sequential monolayer deposition V = vacuum. 

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