Carrier concentration and mobility in B doped Si1−xGex

Hall effect measurements in the 4–300 K temperature range have been used to investigate the electrical properties of B doped Si1−xGex layers (with 0≤x≤0.2) grown on Si(100) by MBE. The Hall concentration and mobility of strained and relaxed Si1−xGex layers have been converted into carrier concentration and drift mobility using the appropriate Hall scattering factor rH that has been determined by the comparison between the chemical B concentration profile (measured by secondary ion mass spectrometry) and the Hall carrier concentration. The mobility of both relaxed and strained layers was equal to that of Si and independent of the Ge concentration for x<0.2 and B concentration ≥1018 cm−3. The Hall scattering factor as a function of temperature has been determined.