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Electron transport in Si/SiGe modulation-doped heterostructures using Monte Carlo simulation

F. Monsef·P. Dollfus·S. Galdin-Retailleau·H. -J. Herzog·T. Hackbarth
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Abstract

The electron transport in the two-dimensional gas formed in tensile-strained Si1-xGex/Si/Si1-xGex heterostructures is investigated using Monte Carlo simulation. At first the electron mobility is studied in ungated modulation doped structures. The calculation matches very well the experimental results over a wide range of electron density. The mobility typically varies between 1100 cm2/Vs in highly-doped structures and 2800 cm2/Vs at low electron density. The mobility is shown to be significantly influenced by the thickness of the spacer layer separating the strained Si channel from the pulse-doped supply layers. Then the electron transport is investigated in a gated modulation-doped structure in which the contribution of parasitic paths is negligible. The mobility is shown to be higher than in comparable ungated structures and dependent on the gate voltage, as a result of the electron density dependence of remote impurity screening.

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F. Monsef, P. Dollfus, S. Galdin-Retailleau, H. -J. Herzog, T. Hackbarth. 2003-12-17. Electron transport in Si/SiGe modulation-doped heterostructures using Monte Carlo simulation. https://doi.org/10.1063/1.1650885

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