Solid phase epitaxy

Japanese researchers are ahead of their U.S. counterparts in the application of laser and electron beams and solid-phase epitaxy for the fabrication of silicon-on-insulator structures. 

Solid oxide fuel cell(s) (SOFCs), 12 201, 204, 205, 223-227, 13 845, 860-861 Solid-phase epitaxy, 14 447 Solid phase extraction (SPE)... 

Solid-Phase Chemical Equilibrium. For the growth of multicomponent films, the solid film composition must be predicted from the gas-phase composition. In general, this prediction requires detailed information about transport rates and surface incorporation rates of individual species, but the necessary kinetics data are rarely available. On the other hand, the equilibrium analysis only requires thermodynamic data (e.g., phase equilibrium data), which often are available from liquid-phase-epitaxy studies, as discussed by Anderson in Chapter 3. 

Epitaxial Layers. Epitaxial deposition produces a single crystal layer on a substrate for device fabrication or a layer for multilevel conductive interconnects which may be of much higher quality than the substrate. The epitaxial layer may have a different dopant concentration as a result of introducing the dopant during the epitaxial growth process or may have a different composition than the substrate as in silicon on sapphire. Methods used for epitaxial growth include chemical vapor deposition (CVD), vapor phase epitaxy (VPE), liquid phase epitaxy (LPE), molecular beam epitaxy (MBE) and solid phase epitaxy (SPE). 

Current research interest is in the solid phase epitaxial regrowth of amorphous Si using laser processing. RBS has been used to follow the melting and recrystallization of the crystal-amorphous interface (12). This is accomplished by monitoring the backscattered spectrum+with the substrate oriented in a direction that will allow the He to channel along the crystal planes. 

In the first chapter, we consider the fundamental nature of the thermally-induced CVD. Initially, we consider the behavior of CVD reactions under the assumption of chemical equilibrium. Much useful information can be derived by this technique, especially for very complex chemical systems where several different solid phases can be deposited. In order to extend our understanding of CVD, it is necessary to consider reacting gas flows where the rates of chemical reactions are finite. Therefore, the next subject considered is the modeling of CVD flows, including chemical kinetics. Depending on processing conditions, the film being deposited may be amorphous, polycrystalline, or epitaxial. 

K. Radermacher, S. Mantl, Ch. Dieker, H. Ltith, C. Freiburg. Growth kinetics of iron silicides fabricated by solid phase epitaxy or ion beam synthesis // Thin Solid Films.- 1992.-V.215, No.l.- P.76-81. 

To obtain this composition, a metallic solvent is contacted with a silicon source at this temperature Ta during few hours. This leads to the saturation of the solvent in Si, at Xa concentration. Then, the silicon source is removed. If this liquid is brought into contact with a silicon substrate at this temperature, the equilibrium is not changed. However, when the solution is cooled down to Tb, the system presents two phases silicon solid phase appears and the new concentration of the liquid phase in Si becomes Xc. If the cooling process is slow (few Kelvin per minute or less), parasite germination rate within the solvent is close to zero and epitaxial deposition of silicon occurs only on the substrate. 

A solid phase extended upon another solid support may not possess its normal lattice structure due to epitaxial effects it may be more stable as a sheet of leptons, as a patchwork of small two-dimensional platelets, or as disseminated, isolated leptons. 

Fig. 10.3. Solid-phase epitaxial regrowth versus anneal time for an amorphous-implanted layer on (100) oriented single crystalline Si...

Fig. 10.6. Growth rate versus 1/kT for solid-phase epitaxial regrowth of implanted amorphous Si on (100) Si (from Olson and Roth 1988)...

All vapor phase epitaxial growth processes involve the interaction of the vapor with the surface of the solid phase, thereby demanding the inclusion of heterogeneous kinetics into the overall rate discussion. The typical description of surfaces is a model based on the hypothesis that surfaces are composed of a fixed number of sites on which... 

Phase Transitions in Metal Oxide Catalysts- As alluded to above, several changes in solid structure can occur that can result in the loss of catalydcally active surface. For oxides on oxide supports, the individual solid phases may be active or a specific mixed oxide phase (such as a spinel or trirutile) may be more active than the segregated phases. Between these two extremes, many oxide catalysts are formed by monolayer epitaxy of an active surface oxide layer on a sympathetic support so that the support intimately but not directly promotes the formation of the active surface. 

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