Upper limit of two-dimensional hole gas mobility in strained Ge/SiGe heterostructures

High two-dimensional hole gas (2DHG) mobility (μ2DHG>10000cm2/Vs at T<100K) strained Ge/Si1−xGex structures with x=0.5 and 0.65 were fabricated, and temperature dependence of their 2DHG mobility was obtained experimentally by the mobility spectrum analysis of the conductivity under magnetic fields. The theoretically calculated 2DHG mobility was compared to experimental data to determine the effective deformation potentials for scattering by acoustic and optical phonons. Using empirically confirmed parameters, the upper theoretical limit of room temperature 2DHG mobility μ2DHG in strained Ge as a function of strain was calculated. The possibility to achieve μ2DHG>5000cm2/Vs at room temperature is presented.