A method of fabricating a semiconductor device includes forming a fin extruding from a substrate, the fin having a plurality of sacrificial layers and a plurality of channel layers, wherein the sacrificial layers and the channel layers are alternately arranged; removing a portion of the sacrificial layers from a channel region of the fin; depositing a spacer material in areas from which the portion of the sacrificial layers have been removed; selectively removing a portion of the spacer material, thereby exposing the channel layers in the channel region of the fin, wherein other portions of the spacer material remain as a spacer feature; and forming a gate structure engaging the exposed channel layers.