Aluminum nitride (AlN) film coatings have been obtained by a new technique of hybrid helikon-arc ion-plasma deposition. Possibility to combine the magnetic-filtered arc plasma deposition technique with a treatment in RF plasma of helicon discharge allowed us to deposit AlN coatings on thermolabile substrates, significantly increasing the deposition rate. A study of spectral properties of AlN films (reflection and transmission spectra within the range 2…25 µm) has been carried out by using the infrared Fourier spectrometer Spectrum BX-II. It has been shown that the obtained composite structures (AlN coatings on teflon and mylar substrates) could be used as passive filters in the infrared spectral range.