A method of operating a deposition apparatus is provided. The method comprises: Deposition of an evaporated source material on a substrate by guiding the evaporated source material from one or more outlets of an evaporation source toward the substrate, wherein part of the evaporated source material is blocked by and attaches to a shielding device arranged between the one or more outlets and the substrate, followed by a cleaning of the shielding device by at least locally heating the shielding device for releasing at least part of the attached source material from the shielding device. According to a further aspect, a deposition apparatus is provided that can be operated according to the described methods.