In a method for depositing layers on one or more substrates arranged in a process chamber, at least one carbon-containing gaseous source material is used in at least one deposition step. During layer growth on the one or more substrates, parasitic coatings are also deposited on the wall surfaces of the process chamber. After removing the one or more substrates from the process chamber, a gas flow containing one or more cleaning gases is introduced into the process chamber and the process chamber is heated to a cleaning temperature. The parasitic coatings are transformed into volatile substances, which are removed from the process chamber with the gas flow. To remove a carbon-containing residue on the wall surfaces, an ammonia cleaning step is performed in which the carbon-containing residue reacts with ammonia to form a volatile compound which is removed from the process chamber with the gas flow.