A semiconductor structure is provided that includes a fin structure of, from bottom to top, a semiconductor punch through stop (PTS) doping fin portion, a dielectric material fin portion, and a topmost semiconductor fin portion that is present on a wider semiconductor fin base. A functional gate structure straddles the semiconductor fin structure. Portions of the wider semiconductor fin base that are not located directly beneath the fin structure of the present application and that are not covered by the functional gate structure can be used as an area for epitaxial growth of source/drain structures. The wide semiconductor fin base improves source/drain epitaxy for better dopant incorporation and strain enhancement.