Sputtered zinc oxide thin films deposited on polyimide substrate and annealing effect on the physical characteristics

The crystalline structure of the annealed ZnO films exhibited strong orientation along the c axis, with the (002) plane parallel to the kapton substrate. The electrical conductivity of these films, before annealing, has a value between 1.63 and 2.48 × 10− 4 Ω− 1 cm− 1.The optical analyses were investigated by measuring the transmittance curves that were used to find the optical bandgap energy. Post-deposition annealing of the ZnO/kapton samples led to an increase in the optical bandgap from 3.19 to 3.24 eV, emphasizing that annealing and nature of the substrate influence the characteristics of the thin film.