The invention relates to a method for removing carbon layers, in particular ta-C layers, from substrate surfaces of tools and components. The substrate to be de-coated is accordingly arranged on a substrate support in a vacuum chamber, the vacuum chamber is charged with at least one reactive gas assisting the evacuation of carbon in gaseous form and a low-voltage plasma discharge is created in the vacuum chamber to activate the reactive gas and hence assist the required chemical reaction or reactions to de-coat the coated substrate. The low-voltage plasma discharge is a dc low-volt arc discharge, the substrate surfaces to be de-coated are bombarded substantially exclusively with electrons and oxygen, nitrogen and hydrogen are used as reactive gas.