Methods of forming semiconductor devices include forming a lower dielectric layer, to a height below a height of a dummy gate hardmask disposed across multiple device regions, by forming a dielectric fill to the height of a dummy gate and etching the dielectric fill back. A dummy gate structure includes the dummy gate and the dummy gate hardmask. A protective layer is formed on the dielectric layer to the height of the dummy gate hardmask. The dummy gate hardmask is etched back to expose the dummy gate.