NOVELTY - Fabricating a thin film photovoltaic solar energy collector film involves providing a substrates (208); transferring the substrates into a furnace; introducing a gaseous species including a selenide species and a carrier gas into the furnace and transferring thermal energy into the furnace to at least initiate formation of a copper indium diselenide film; maintaining the temperature at the second temperature; removing at least residual selenide species; introducing a sulfide species into the furnace; and increasing a temperature to a third temperature.    USE - For fabricating a thin film photo-voltaic solar energy collector film (claimed) useful in solar cell.    ADVANTAGE - The method provides benefits of the quantum efficiency and the conversion efficiency; provides a cost-effective method for making thin film solar cell panel; and provides large scale processing of copper indium diselenide species (CIS), and copper indium gallium diselenide species (CIGS) based thin film overlaying glass substrates.    DETAILED DESCRIPTION - Fabricating a thin film photovoltaic solar energy collector film involves providing a substrates (208), where each of the substrates having a copper and indium composite structure (200); transferring the substrates into a furnace, where each of the substrates provided in a vertical orientation with respect to a direction of gravity, the substrates are defined by a number N, where N is greater than 5; introducing a gaseous species including a selenide species and a carrier gas into the furnace and transferring thermal energy into the furnace to increase a temperature from a first temperature to a second temperature, where second temperature is 350-450 degrees C to at least initiate formation of a copper indium diselenide film from the copper and indium composite structure on each of the substrates; maintaining the temperature at the second temperature for a period of time; removing at least residual selenide species from the furnace; introducing a sulfide species into the furnace; and increasing a temperature to a third temperature i.e. 500-525 degrees C, while the substrates are maintained in an environment including a sulfur species to extract out at least one selenium species from the copper indium diselenide film; where the removing of residual selenide species from the furnace occurs until the furnace is in a vacuum configuration. The copper and indium composite structure comprises a copper layer and an indium layer of material. The selenide species comprises hydrogen selenide (H2Se) gas. The carrier gas comprises nitrogen gas. The sulfide species comprise hydrogen sulfide (H2S) gas. The substrate further comprises gallium material.    DESCRIPTION OF DRAWING(S) - The figure shows view of composite structure including a copper and indium film.    Structure (200)    Indium layer (202)    Copper layer (204)    Metal layer (206)    Substrate (208)