Lattice matched system

Figure 8.2 shows schematically an example of a perfect lattice matched system in which atomic diameters are identical, and an example of a mismatch in which atomic diameters are drawn differing by 15% and for which a dislocation has formed. In a poorly matched system, atoms across the interface are in poor registry. This leads to high interfacial stress and high interfacial energy. Interfacial stress is relieved by periodic formation of dislocations [49]. In general, a lattice match of better than approximately 15% is required for a coherent interface [49]. 

Quantum well lasers ia this system typically use ternary Iuq 53GaQ 47AS wells and biaary InP barriers. AH quaternary lasers, ie, lasers ia which both the wells and barriers are formed by quaternary compounds, are also being developed. These stmctures can be lattice matched or strained. 

While there are mairy variants of the basic, model, one can show that there is a well-defined minimal set of niles that define a lattice-gas system whose macroscopic behavior reproduces that predicted by the Navier-Stokes equations exactly. In other words, there is critical threshold of rule size and type that must be met before the continuum fluid l)cliavior is matched, and onec that threshold is reached the efficacy of the rule-set is no loner appreciably altered by additional rules respecting the required conservation laws and symmetries. 

Another quaternary in this system is Ini 3,(ALi Gai- ) v As, which can be grown lattice matched to InP substrates. These materials are grown by MOCVD using the precursors cited above with the addition of TMA1. Recently, this quaternary has shown promise for the growth of advanced high-performance injection lasers operating... 

In principle GaAso. N0.2 can be lattice matched to Si. However, a large miscibility gap exists in this alloy system and these materials tend to phase separate when the N composition is significant [32] as... 

Narayan (2005) TEM ZnO-sapphire Ge-Si systems Epitaxy and other lattice matching concepts + + n.a. Thin film growth, nanostructuring... 

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