A method for formation of a carbon-based field effect transistor (FET) includes depositing a first dielectric layer on a carbon layer located on a substrate; forming a gate electrode on the first dielectric layer; etching an exposed portion of the first dielectric layer to expose a portion of the carbon layer; depositing a second dielectric layer over the gate electrode to form a spacer, wherein the second dielectric layer is deposited by atomic layer deposition (ALD), and wherein the second dielectric layer does not form on the exposed portion of the carbon layer; forming source and drain contacts on the carbon layer and forming a gate contact on the gate electrode to form the carbon-based FET.