described is a method of treating or coating homogeneously at least a portion of the surface of a material selected from metallic materials having a thickness of less than 100 μm and / or polymeric materials . the method of the present invention comprises exposing at least a portion of the surface of the material to an atmospheric plasma generated by an indirect plasmatron . in the method of the present invention , the surface of the material may undergo at least one of an increase in surface tension , a surface grafting , a surface cleaning and a surface sterilization .