Ceramics deposition

As outlined in Sect. 5.2, many attempts have been made to deposit ZnO-based films by sputtering. The compilation of papers in Table 5.1 may serve as a reference to identify useful papers. The classification criteria are plasma excitation used (DC/MF/RF) reactive or ceramic deposition material deposited and film properties relevant for TCO applications. 

Vasiliev, A.L., Padture, N.P., and Ma, X.Q. (2006a) Coatings of metastable ceramics deposited by solution-precursor plasma spray I. Binary Zr02-Al203 system. Acta Mater., 54 (18), 4913-4920. 

Table 10-2 A comparison of various kinds of ceramic deposition technologies.

It is expected that structural relaxation amplitude would increase when higher temperatures and longer annealing periods are employed for the treatments of ceramic Mts. Let us consider that different thermomechanical routes are used for the two panels (front and back). This is the case in practice since the ceramics deposited on both substrates are different and hence have to be treated dififerendy. Both panels experience structural relaxation. Let us call the change in fictive temperature A7 and AT for the front and back plates respectively. Since the thermomechanical routes are different, we have Ajj- ATf. This will... 

To retain the lubricants and thus prevent corrosion, the surfaces of a piece of equipment can be roughened by shot blasting (very fine), blast peening, or application of various porous surfactants (electrodeposited porous metals, clad porous metals, anodizing, phosphatizing, ceramic deposition, or lining). 

Technical ceramics are composed of raw materials generally as powder and of natirral or synthetic chemical additives, favoring either compaction (hot, cold or isostatic), or setting (hydraulic or chemical) or accelerating sintering processes. According to the formulation of the bioceramic and the shaping process used, we can obtain ceramics, dense or with variable porosity, cements, ceramic depositions or ceramic composites. 

MS-SOFCs are prepared by wet ceramic deposition techniques. Densification of the electrolyte requires at least one firing step in reducing atmosphere at high temperature. This route is often referred to as high temperature process . 

MS-SOFCs are prepared by a mixedprocess combining wet ceramic deposition techniques for producing alloy and anode layers and film deposition techniques for coating of the electrolyte. 

In this processes, the alloy support, the AFL, and the electrolyte are prepared by wet ceramic deposition techniques (see Fig. 10). The assembly is subjected to one... 

Cornish, D.C., A probe electrode technique for controlling the thickness of electrophoretic ceramic deposits. J. Sci. Instrum. (J. Phys. E) 2 123-4 (1969). 

Electrophoretic deposition (EPD) is anotlier metliod of casting slurries. EPD is accomplished tlirough tire controlled migration of charged particles under an applied electric field. During EPD, ceramic particles typically deposit on a mandrel to fonn coatings of limited tliickness, or tliin tubular shapes such as solid (3 " - AI2O2 electrolytes for sodium-sulfur batteries. 

J. B. MacChesney, P. B. O Connor, P. V. DiMarceUo, J. R. Simpson, and P. D. La2ay, "Preparation of Low-Loss Optical Pibers Using Simultaneous Vapor-Phase Deposition and Pusion," in Proceedings of t/je Tent/j Internationa/ Congress on G/ass, Ffoto, Japan, Vol. 6 Ceramics Society, Japan, 1974, pp. 50—54. 

Molybdenum hexafluoride is used in the manufacture of thin films (qv) for large-scale integrated circuits (qv) commonly known as LSIC systems (3,4), in the manufacture of metallised ceramics (see MetaL-MATRIX COMPOSITES) (5), and chemical vapor deposition of molybdenum and molybdenum—tungsten alloys (see Molybdenumand molybdenum alloys) (6,7). The latter process involves the reduction of gaseous metal fluorides by hydrogen at elevated temperatures to produce metals or their alloys such as molybdenum—tungsten, molybdenum—tungsten—rhenium, or molybdenum—rhenium alloys. 

Fused Salt Electrolysis. Only light RE metals (La to Nd) can be produced by molten salt electrolysis because these have a relatively low melting point compared to those of medium and heavy RE metals. Deposition of an alloy with another metal, Zn for example, is an alternative. The feed is a mixture of anhydrous RE chlorides and fluorides. The materials from which the electrolysis cell is constmcted are of great importance because of the high reactivity of the rare-earth metals. Molybdenum, tungsten, tantalum, or alternatively iron with ceramic or graphite linings are used as cmcible materials. Carbon is frequently used as an anode material. 

Fig. 2. The Dow magnesium cell. The steel container. A, is equipped with a ceramic cover, B, through which graphite anodes, C, pass. The magnesium is deposited on the cathode, D, and is diverted as it rises into the collection sump, E. The chlorine is withdrawn through a vent, F.

Slip casting of metal powders closely follows ceramic slip casting techniques (see Ceramics). SHp, which is a viscous Hquid containing finely divided metal particles in a stable suspension, is poured into a plaster-of-Paris mold of the shape desired. As the Hquid is absorbed by the mold, the metal particles are carried to the wall and deposited there. This occurs equally in all directions and equally for metal particles of all sizes which gives a uniformly thick layer of powder deposited at the mold wall. 

Fused-salt electrolysis of K2NbFy is not an economically feasible process because of the low current efficiency (31). However, electrowinning has been used to obtain niobium from molten alkaU haUde electrolytes (32). The oxide is dissolved in molten alkaU haUde and is deposited in a molten metal cathode, either cadmium or zinc. The reaction is carried out in a ceramic or glass container using a carbon anode the niobium alloys with the cathode metal, from which it is freed by vacuum distillation, and the niobium powder is left behind. 

Cadmium Sulfide Photoconductor. CdS photoconductive films are prepared by both evaporation of bulk CdS and settHng of fine CdS powder from aqueous or organic suspension foUowed by sintering (60,61). The evaporated CdS is deposited to a thickness from 100 to 600 nm on ceramic substates. The evaporated films are polycrystaUine and are heated to 250°C in oxygen at low pressure to increase photosensitivity. Copper or silver may be diffused into the films to lower the resistivity and reduce contact rectification and noise. The copper acceptor energy level is within 0.1 eV of the valence band edge. Sulfide vacancies produce donor levels and cadmium vacancies produce deep acceptor levels. 

Pt(CO)2Cl2] is used to deposit thin films of metallic platinum on surfaces. Concentiated organic solutions of poorly defined platinum complexes of alkyl mercaptides or sulforesinates are used to coat ceramics and glass. 

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