Crystal growth methods

Epitaxial crystal growth methods such as molecular beam epitaxy (MBE) and metalorganic chemical vapor deposition (MOCVD) have advanced to the point that active regions of essentially arbitrary thicknesses can be prepared (see Thin films, film deposition techniques). Most semiconductors used for lasers are cubic crystals where the lattice constant, the dimension of the cube, is equal to two atomic plane distances. When the thickness of this layer is reduced to dimensions on the order of 0.01 )J.m, between 20 and 30 atomic plane distances, quantum mechanics is needed for an accurate description of the confined carrier energies (11). Such layers are called quantum wells and the lasers containing such layers in their active regions are known as quantum well lasers (12). 

List the ways that one ean obtain a "seed" crystal. Is it possible to use one t37pe of crystal-growth method to obtain a seed crystal for Czochralski growth ... 

Crystal Growth. Depending on the materials, two types of crystal growth method have been used solution for AMA and POM, melt for MAP and NPP. 

Double-jet crystal growth method, 19 179 Double-layer compression, 11 631 Double-layer forces, flocculation and,... 

Triphenyltin, as skin irritant, 24 829 Triphenyltin hydroxide, 24 817 as eye irritant, 24 829 Triphenymethane soluble dyes, 7 373t Triphosphorus pentanitride, 79 57 Triple bottom line, 72 807 Triple-bond stretching, 74 235 Triple helices, 77 609 Triple-helix formation, 77 528 Triple-jet crystal growth methods,... 

The figure on the inner front cover of this book can be used to convert between doping density, carrier mobility and resistivity p for p- or n-type doped silicon substrates. One of the major contaminants in silicon is oxygen. Its concentration depends on the crystal growth method. It is low in FZ material and high (about 1018 cm-3) in Czochralski (CZ) material. 

NH4)2S2Os NH HCOj Al3+ and Fe3+ lead to needle formation removal of admixtures crystal growth methods of crystallising coarse grained, stabilisation... 

Carter, C.W.J. 1997. Response surface methods for optimizing and improving reproducibility of crystal growth. Methods Enzymol 276 74-99. 

All of the general precautions that hold for chemical crystal growth methods (Section III.A.l) must be observed in electrocrystallization experiments also (purity of starting materials and solvent light- and vibration-free environment). If a radical-cation salt is to be prepared, 5 mL of donor solution (1 to 5 mM) is placed in the half-cell that contains the anode. 

Figure 36 Schematic of the Bridgeman crystal growth method (a). Vemeuil crystal growth method (b)...

Metal Aqua Ions (G. Sykes et al.). Solvents and Ionic Liquids (P.J. Dyson). Chromatographic Methods (R. Shepherd). Crystal Growth Methods (W. Clegg). 

Ducruix AF and Reis-Kautt MM. Solubility Diagram Analysis and the Relative Effectiveness of Different Ions on Protein Crystal Growth. Methods A Companion to Methods in Enzymology. 1990 1(1) 25-30. 

Crystal growth of low-temperature forms of materials requires its own specific processes. For examples, a-quartz is an interesting material because of its piezoelectric properties. The a- transition is close to 573 °C a high-pressure hydrothermal, crystal-growth method has been developed because the application of pressure increases the solubility of the nutrient. Such a process is shown in Fig. 7.15. The difference in temperature, AT, between the upper part of the reaction vessel (which contains the seeds) and the lower part (containing the nutrient) provides the driving force of the chemical transport for the crystal-growth process. 

Advances in epitaxial crystal growth methods make it possible to prepare heterostructures with essentially arbitrary thiekness of the small-gap layer. When the thickness of this layer is reduced to dimensions of the order of 10 nm (between 20 and 30 atomic planes) a quantum mechanical description of the confined carriers is needed. Such heterostructures are called quantum wells [41. 42]. 

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