An extremely high room temperature mobility of two-dimensional holes in a strained Ge quantum well heterostructure grown by reduced pressure chemical vapor deposition

An extremely high room temperature two-dimensional hole gas (2DHG) drift mobility of 4230 cm²V-1 s-1 in a compressively strained Ge quantum well (QW) heterostructure grown by an industrial type RP-CVD technique on a Si(001) substrate is reported. The low-temperature Hall mobility and carrier density of this structure, measured at 333 mK, are 777000cm2V-1 s-1 and 1.9×1011cm-2, respectively. These hole mobilities are the highest not only among the group-IV Si based semiconductors, but also among p-type III-V and II-VI ones. The obtained room temperature mobility is substantially higher than those reported so far for the Ge QW heterostructures and reveals a huge potential for further application of strained Ge QW in a wide variety of electronic and spintronic devices.