Methods and structures for forming semiconductor FinFET devices with superior repeatability and reliability include providing APT (anti-punch through) layer accurately formed beneath a semiconductor fins, are provided. Both the n-type and p-type APT layers are formed prior to the formation of the material from which the semiconductor fin is formed. In some embodiments, barrier layers are added between the accurately positioned APT layer and the semiconductor fin. Ion implantation methods and epitaxial growth methods are used to form appropriately doped APT layers in a semiconductor substrate surface. The fin material is formed over the APT layers using epitaxial growth/deposition methods.