FinFETs and methods for making FinFETs are disclosed. A fin is formed on a substrate, wherein the fin has a height greater than 2 to 6 times of its width, a length defining a channel between source and drain ends, and the fin comprises a lightly doped semiconductor. A conformally doped region of counter-doped semiconductor is formed on the fin using methods such as monolayer doping, sacrificial oxide doping, or low energy plasma doping. Halo-doped regions are formed by angled ion implantation. The halo-doped regions are disposed in the lower portion of the source and drain and adjacent to the fin. Energy band barrier regions can be formed at the edges of the halo-doped regions by angled ion implantation.