Various semiconductor devices are disclosed. An exemplary device includes: a substrate; a gate structure disposed over the substrate, wherein the gate structure includes a source region and a drain region; a first etch stop layer disposed over the gate structure, a second etch stop layer disposed over the source region and the drain region; a dielectric layer disposed over the substrate; and a gate contact, a source contact, and a drain contact. The dielectric layer is disposed over both etch stop layers. The gate contact extends through the dielectric layer and the first etch stop layer to the gate structure. The source contact and the drain contact extend through the dielectric layer and the second etch stop layer respectively to the source region and the drain region.