Motivation of this work is to deposit thin film by thermal evaporation technique that involves heating a solid material inside a highly vacuum chamber, at a temperature that produces vapor pressure yielding to an adhesive force enough for the film to be grown on the substrate. The system incorporates a vacuum chamber with a heater which raises the temperature to a sufficient level to deposit thin film on desired substrate. On the contrary, to maintain the system in an effective cost extent the instrumental set up is customized. Therefore, constituents of the system such as heating chamber, heater, vacuum-pump and steel substrate holder are designed with easily available equipment according to the pre-requirement without any kind of downfall in the quality of the thin film. Afterwards Zinc Oxide thin film is obtained by controlling the necessary parameters for thermal evaporation technique with this system followed by the measurement of optical characteristics and band gap energy of deposited thin film by Spectrophotometer.