Lateral transport in strained SiGe quantum wells doped with boron

The temperature dependence of conductivity and hole mobility in boron doped SiGe quantum well structures was studied. The conductivity at low temperatures is shown to be due to hopping over neutral B centers while at higher temperatures, it is due to two-stage excitation including thermal activation of holes from the ground to strain-split B states following by hole tunneling into the valence band. Inclining the valence bands of investigated QW structures makes possible to find the energy splitting of acceptor levels by strain from the temperature dependence of conductivity.