NOVELTY - A CIGS thin film (50) is formed on a substrate (40). Pneumatic cylinder(s) (10) is used to apply a pressure in the non-vacuum environment for driving a holder (20) connected to the cylinder. The holder drives at least one roller (30) to press on the upper surface of the substrate. The substrate is moved back and forth to uniformly roll the roller on the thin film to compact. The roller is a ceramic roller, or an outer surface of the roller is processed with a thermal treatment, or the outer surface of the roller is provided with a hard coating layer.    USE - Compacting of copper/indium/gallium/selenium (CIGS) thin film of solar cells in non-vacuum environment.    ADVANTAGE - The method enables uniform compacting by setting the diameter of roller to preset value. The outer surface of roller is thermally treated to avoid damages caused by broken glass. The hard coating layer avoids adverse effects caused by sharp stuff or broken chips.    DETAILED DESCRIPTION - A CIGS thin film is formed on an upper surface of a substrate serving as a light absorbing layer. At least one pneumatic cylinder is used to apply a pressure in the non-vacuum environment for driving a holder connected to the cylinder. The holder drives at least one roller fixed to the holder downward to press on the upper surface of the substrate. The substrate is moved back and forth to uniformly roll the roller on the thin film to compact the thin film. The thin film is obtained from a deposited CIGS slurry or ink containing CIGS material, and processed by a soft baking process. The roller is a ceramic roller, or an outer surface of the roller is processed with a thermal treatment to improve hardness of the outer surface, or the outer surface of the roller is provided with a hard coating layer for protecting the outer surface of the roller. An INDEPENDENT CLAIM is included for compacting apparatus.    DESCRIPTION OF DRAWING(S) - The drawing shows a schematic view of the method and apparatus used for compacting CIGS thin film.    Pneumatic cylinder (10)    Holder (20)    Roller (30)    Substrate (40)    CIGS thin film (50)