US Patent 10164053 Semiconductor device and method

In an embodiment, a method includes: forming a gate stack on a semiconductor fin, the gate stack having gate spacers along opposing sides of the gate stack; forming source/drain regions adjacent the gate stack; recessing the gate stack to form a first recess between the gate spacers; depositing a dielectric layer over the gate stack in the first recess; forming a first metal mask over the dielectric layer and the gate stack in the first recess; etching back the dielectric layer and the gate spacers to form a dielectric mask under the first metal mask; depositing a conductive material over the first metal mask and adjacent the gate stack; and planarizing the conductive material to form contacts electrically connected to the source/drain regions, top surfaces of the contacts and the dielectric mask being level.