Junctions metal-ceramic

A p-n combination is referred to as a couple. To fabricate the TEC, a number of couples, up to 100, are placed in series, electrically, and in parallel, thermally, between two metallized ceramic plates as shown in Figure 3.16. The completed assembly acts as a heat pump. When the junctions are biased on, one side (the cold jxmction) removes heat from the heat source whereas the other side (the hot jxmction) increases in temperature. Typically, a heat sink is placed on tixe hot jxmction side to transport the heat to ambient. 

MOSFETs. A type of semiconductor device that utilizes oxide ceramics is a metal-oxide-semiconductor field-effect transistor, abbreviated as MOSFET. Just like the semiconductor junction devices of Section 6.1.1.6, the MOSFET is composed of n-and / -type semiconductor regions within a single device, as illustrated in Figure 6.36. 

The competition between the interfacial reactivities, the residual stresses and the elasto-plastic behavior of the components will be strongly dependent on the mechanical stability of the coating-substrate combination. Mechanical stability control has been assessed when making ceramic/metal junctions at high temperature (700°C - 1000°C) during which thick reaction zones tend to form by reactive diffusion in volume intermediate layers. ... 

The problem of lateral modification of HTSC surface layers, and the local electrosynthesis of HTSCs on the surface of patterned substrates including the precursors is very interesting. Such processes can occur, for example, during electrooxidation of metals when the process in its initial stages takes place only on isolated microscopic regions. Thus, Josephon junctions on the surface of Bi-Sn alloys [222] and on ceramic YBCO samples [295,444] were obtained by using electrochemical oxidation without any special local techniques. But it is hard to control such oxidation processes, and sufficient reproducibility cannot be ensured for most systems. Josephson tunnel junctions based on electrochemically synthesized BKBO crystals have been described [445]. 

Hallab NJ. Messina C. Skipor A, Jacobs JJ. Differences in the fretting corrosion of metal-metal and ceramic-metal modular junctions of total hip replacements. Journal of Orthopaedic Research 2004 22(2) 250-9. 

A useful avalanche diode that works in either direction is the "varistor," sometimes called the "metal oxide varistor," or "MOV." It is not just a single crystal device as the previously described semiconductors are, but instead it is polycrystalline ceramic material, usually zinc oxide, with many small PN junctions at the grain boundaries. It is quite inexpensive and is very rugged, so it can be found as an important part inside most "surge protector power strips" for connecting multiple computer modems, printers, etc., to protect them against inductive kicks and even most "spikes" ("transients") from lightning. ... 

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