Alloying and carrier mobility

Several processes contribute to the mobility behavior in the alloy. The mobility is reduced by alloy scattering due to fluctuations in the atomic core potentials. Also, in biaxially strained thin films the cubic symmetry of the solid is eliminated by the strain field, and individual branches of the band structure are split to different energies. This reduces scattering from one band to another near the band minimum and consequently increases mobility. Alloy scattering dominates the behavior overall. 

Although the carrier mobilities are reduced in thin film and bulk alloys relative to the pure semiconductors, mobilities within very thin quantum well structures can be significantly enhanced by reduction in possible scattering directions. Thus, artificially structuring thin films of alloys can recover and even improve the performance of the material. 

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