Plasma processes during CN x films deposition were studied in a pulsed laser deposition system equipped with a KrF excimer laser (500 mJ, 20 ns). The laser plasma was characterized in a pressure range from 2 to 100 Pa of nitrogen gas. We report on an optical emission spectroscopy, which was used for a spatial and time resolved investigation of the plasma species. Analysis includes estimation of vibrational and rotational temperatures of the CN molecule.