A method includes removing a first portion of a dummy gate structure over a first fin while keeping a second portion of the dummy gate structure over a second fin, where removing the first portion forms a first recess exposing the first fin, forming a first gate dielectric material in the first recess and over the first fin, and removing the second portion of the dummy gate structure over the second fin, where removing the second portion forms a second recess exposing the second fin. The method further includes forming a second gate dielectric material in the second recess and over the second fin, the second gate dielectric material contacting the first gate dielectric material, and filling the first recess and the second recess with a conductive material.