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arXiv · 0908.0552

Intersubband carrier scattering in n- and p-Si/SiGe quantum wells with diffuse interfaces

A. Valavanis·Z. Ikonić·R. W. Kelsall
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Abstract

Scattering rate calculations in two-dimensional Si/SiGe systems have typically been restricted to rectangular Ge profiles at interfaces between layers. Real interfaces, however, may exhibit diffuse Ge profiles either by design or as a limitation of the growth process. It is shown here that alloy disorder scattering dramatically increases with Ge interdiffusion in (100) and (111) n-type quantum wells, but remains almost constant in (100) p-type heterostructures. It is also shown that smoothing of the confining potential leads to large changes in subband energies and scattering rates, and a method is presented for calculating growth process tolerances.

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A. Valavanis, Z. Ikonić, R. W. Kelsall. 2009-08-04. Intersubband carrier scattering in n- and p-Si/SiGe quantum wells with diffuse interfaces. https://doi.org/10.1103/physrevb.77.075312

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