InAs/InP core/shell nanowires with different shell thicknesses were grown by a two-step method, and large-scale assembly of single nanowire was realized by using dielectrophoresis alignment and patterned grooves. Thousands of single nanowire field-effect transistors were fabricated on a single chip. The effect of InP shell thickness on the electron mobility and density of InAs nanowires are experimentally investigated and discussed.