NOVELTY - A material for depositing film is placed in device having cuboid chamber provided with four chambers (A-D). Selenium in chamber (B) is heated, heaters corresponding to gallium, indium and copper sources are started and copper-indium-gallium-diselenide film is generated. Selenium in chamber (C) is heated, heaters corresponding to gallium and indium sources are synchronously started, and copper-indium-gallium-diselenide absorbing layer is generated. Evaporation sources in chamber (B) are gallium, indium, sodium and selenium. Evaporation sources in chamber (C) are gallium and indium.    USE - Roll-to-roll method for depositing absorbing layer on flexible substrate used for copper-indium-gallium-diselenide solar cell.    ADVANTAGE - The absorbing layer has favorable adhesiveness and crack resistance. The solar cell containing the substrate deposited with absorbing layer has favorable flexibility.    DETAILED DESCRIPTION - A device for preforming roll-to-roll method for depositing absorbing layer on flexible substrate is prepared as follows. A cuboid chamber as deposition film chamber is welded, two mutually parallel rolling shafts which drive flexible substrate to move is provided at upper portion in the deposition film chamber. Four chambers (A,B,C,D) are provided at bottom surface in the deposition film chamber. A heating plate connecting a thermocouple is placed above the substrates corresponding to the chambers (A,B,C) respectively, and sensors are placed above the substrates of chambers (B,C), and three sensors are formed in a line. A proportional-integral-derivative controller, a vacuumizing pump and a change-speed motor are provided outside the deposition film chamber. A material for depositing the film is placed in the device, different metal elements as evaporation sources is placed in the chamber (A,B,C). Bottom of each evaporation source is connected with heaters connected with the thermocouples. An X-ray florescent spectrograph is built in the chamber (D). Film is deposited on the flexible substrate as follows. The deposition film chamber and four chambers are vaccuumized to less than 1x 10-4 Pa. Each heating plate is controlled using the proportional-integral-derivative controller, the substrate temperature of the chambers (A,B,C,D) are maintained at 350-400 degrees C, 450-500 degrees C and 450-500 degrees C respectively, the temperature of each evaporation source corresponding to the thermocouple measurement is measured, measurement signals are transmitted to the proportional-integral-derivative controller, the proportional-integral-derivative controls relative evaporation source heaters by transmission signals, and a copper-indium-gallium-diselenide layer diffused with sodium atoms is deposited on the substrate. The evaporation sources are sequentially arranged from left to right in the chamber (B) as follows. One of gallium-indium-copper, copper-gallium-indium or gallium-copper-indium, and selenium are located in a leftmost line or a rightmost line, selenium in the chamber (B) is heated at 250-350 degrees C, heaters corresponding to gallium, indium and copper sources in the chamber are started, the heaters are monitored using three sensors in the chamber (B), the monitoring signals are transmitted to the proportional-integral-derivative controller, and proportional-integral-derivative controller controls the relative evaporation source heaters by the transmission signals, such that copper-indium-gallium-diselenide chemical phase film is generated. When selenium in the chamber (C) is heated to 250-350 degrees C, the heaters corresponding to gallium and indium sources are synchronously started, the heaters are monitored by three sensors in the chamber (C), the monitoring signals are transmitted to the proportional-integral-derivative controller, and proportional-integral-derivative controller controls the relative evaporation source heaters by the transmission signals, such that copper-indium-gallium-diselenide absorbing layer (Cu(In0.7, Ga0.3)Se2) having micropores, unevenness of less than plus minus 2%,, and thickness of 0.15-1.5 mm. The spectrograph is utilized to perform online detection for components, thickness and uniformity of the copper-indium-gallium-diselenide absorbing layer. One of rolling shafts is taken as an initial rolling shaft and other one is taken as terminal rolling shaft. The evaporation sources are gallium, indium, sodium and selenium. The evaporation sources in the chamber (B) are gallium, indium, sodium and selenium. The evaporation sources in the chamber (C) are gallium and indium. The ratio of copper, and total content of indium and gallium in the copper-indium-gallium-diselenide chemical phase film is more than 1. The ratio of copper and total content of indium and gallium in the copper-indium-gallium-diselenide absorbing layer is more than 1.