A semiconductor structure includes a substrate, a vertical fin disposed over a top surface of the substrate, a first vertical transport field-effect transistor (VTFET) disposed over the top surface of the substrate surrounding a first portion of the vertical fin, an isolation layer disposed over the first VTFET surrounding a second portion of the vertical fin, and a second VTFET disposed over a top surface of the isolation layer surrounding a third portion of the vertical fin. The first portion of the vertical fin includes a first semiconductor layer with a first crystalline orientation providing a first vertical transport channel for the first VTFET, the second portion of the vertical fin includes an insulator, and the third portion of the vertical fin includes a second semiconductor layer with a second crystalline orientation providing a second vertical transport channel for the second VTFET.