The proximity effect of the regrowth interface on two-dimensional electron density in strained Si

Abstract

We studied the density of two-dimensional electron gas (2DEG) in Si∕SiGe heterostructures as a function of the distance between the substrate-epilayer interface and the 2DEG layer. The 2DEG sheet density was observed to change from 2.2×1011to3.5×1011cm−2. Theoretical simulations are shown to be consistent with the experimental results within experimental errors. The slight deviations of the experimental results possibly come from temperature variation of the Sb dopant source during the growth of the Sb doping layer.