Methods for fabricating integrated circuits are provided. In an embodiment, a method for fabricating an integrated circuit includes forming a gate stack on a semiconductor substrate. In the method, a first halo implantation is performed on the semiconductor substrate with a first dose of dopant ions to form first halo regions therein. A second halo spacer is formed around the gate stack. Then a second halo implantation is performed on the semiconductor substrate with a second dose of dopant ions to form second halo regions therein.