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 temperat ures is shown to be due to hopping over neutral B centers while at higher t emperatures, it is due to two-stage excitation including thermal activation of holes from the ground to strain-split B states following by hole tunnel ing into the valence band. Inclining the valence bands of investigated QW s tructures makes possible to find the energy splitting of acceptor levels by strain from the temperature dependence of conductivity.