Transport properties of boron doped tensile strained, perfectly strain comp
ensated and compressively strained Si1-x-yGexCy alloy layers on Si(001) sub
strates are presented. The room temperature mobility decreases with C and G
e alloy concentration compared to pure Si from 180 cm(2)/Vs (p = 3 x 10(17)
cm(-3)) to 120 cm(2)/Vs, which is explained by the increasing alloy scatte
ring and enhanced scattering at optical phonons. At temperatures below 100
K a higher mobility is measured for the samples containing C due to the low
er carrier concentration, and because ionized impurity scattering becomes d
ominant. The temperature dependence of the hole density is used to determin
e the boron activation energy E-A. We observe an activation energy of about
3 meV in Si0.94Ge0.06. With carbon incorporation E-A first decreases to 27
meV and then increases to 36 meV for the strain compensated sample. In mod
ulation doped p-type Si1-x-yGexCy quantum wells, we observe an increased ho
le mobility with C alloying compared to reference samples without C. This i
s a consequence of reduced strain and C induced decreased hole concentratio
n in the quantum well. (C) 1998 Elsevier Science S.A. All rights reserved.