NOVELTY - Preparation of film involves using stainless steel as a base material, cleaning, surface-treating the base material, plating molybdenum-sodium thin film, providing in a vacuum roll-to-roll coating machine, controlling working pressure of sputtering chamber to 5x 10-3 torr using argon gas by throttle valve, sputtering molybdenum-sodium thin film, forming copper-indium-gallium-diselenide absorber layer thin film, plating transparent conductive film, the controlling working pressure of sputtering chamber using argon gas, and sputtering transparent conductive oxide thin film.    USE - Preparation of film used for solar cell.    ADVANTAGE - The method enables efficient preparation of high-quality film having excellent uniformity and performance with high yield and reduced man power.    DETAILED DESCRIPTION - Preparation of film involves using stainless steel having width of 15-150 cm and thickness of less than 1 mm as a base material, cleaning, surface-treating the base material, plating molybdenum-sodium thin film, providing in a vacuum roll-to-roll coating machine, vacuum pumping to 0.7x 10-5-0.9x 10-5 torr in sputtering chamber, using argon gas as working gas, the controlling working pressure of sputtering chamber to 5x 10-3 torr using argon gas by throttle valve, sputtering molybdenum-sodium thin film having thickness of 500 nm on the stainless steel base material by supplying DC power, forming copper-indium-gallium-diselenide absorber layer thin film having a thickness of 2000 nm using roll for rolling common evaporator, heating to 300-550 degrees C, preparing zinc-magnesium oxide film layer by vacuum sputtering, providing the zinc-magnesium oxide film layer in sputtering chamber, vacuum-pumping, to 0.7x 10-5-0.9x 10-5 torr in sputtering chamber, using argon gas as working gas, controlling working pressure of sputtering chamber to 5x 10-3 torr using argon gas by throttle valve, sputtering zinc-magnesium oxide film layer having thickness of 100 nm by supplying RF power, plating transparent conductive film using indium tin oxide in vacuum cavity, vacuum pumping to 0.7x 10-5-0.9x 10-5 torr in sputtering chamber, using argon gas as working gas, the controlling working pressure of sputtering chamber to 5x 10-3 torr using argon gas by throttle valve, and sputtering transparent conductive oxide thin film having thickness of 100 nm by supplying DC power.