Methods of forming gates of semiconductor devices are provided. The methods may include forming a first recess in a first substrate region having a first conductivity type and forming a second recess in a second substrate region having a second conductivity type. The methods may also include forming a high-k layer in the first and second recesses. The methods may further include providing a first metal on the high-k layer in the first and second substrate regions, the first metal being provided within the second recess. The methods may additionally include removing at least portions of the first metal from the second recess while protecting materials within the first recess from removal. The methods may also include, after removing at least portions of the first metal from the second recess, providing a second metal within the second recess.