A method comprises depositing a dielectric layer on sidewalls and a bottom of a trench of a gate structure, depositing a metal layer on the dielectric layer, depositing a protection layer on the metal layer, wherein an upper portion of a sidewall portion of the protection layer is thinner than a lower portion of the sidewall portion of the protection layer and etching back the metal wherein an upper portion of a first metal sidewall of the metal layer is thinner than a lower portion of the first metal sidewall and an upper portion of a second metal sidewall of the metal layer is thinner than a lower portion of the second metal sidewall.