With atmospheric plasma technology, gas is excited by means of a high voltage under atmospheric pressure, such that a plasma is ignited. The plasma is expelled by compressed air from the nozzle. Two plasma effects are differentiated: Activation and ultra-fine cleaning is carried out by the reactive particles contained in the plasma jet. Furthermore, the active gas jet accelerated by compressed air removes loosely adherent particles from the surface. By changing the process parameters such as treatment speed and distance to substrate surface, the treatment results can be influenced.