A method for manufacturing the integrated circuit device including, providing a substrate having a first region and a second region. Forming a dielectric layer over the substrate in the first region and the second region. Forming a sacrificial gate layer over the dielectric layer. Patterning the sacrificial gate layer and the dielectric layer to form gate stacks in the first and second regions. Forming an ILD layer within the gate stacks in the first and second regions. Removing the sacrificial gate layer in the first and second regions. Forming a protector over the dielectric layer in the first region; and thereafter removing the dielectric layer in the second region.