Impact of Annealing Temperature on MnO2 Thin Films: Morphological, Structural, and Electrical Properties

Deposition of the manganese dioxide (MnO2) Thin Film (TF) was carried out by Electron beam (E-beam) evaporation technique. Structural, optical, and electrical characteristics reveal that MnO2 undergoes a phase transformation due to annealing temperature. Photoluminescence (PL) emission reveals the highest intensities at 500°C, indicating the least density of defects present in the sample. Moreover, the XRD analysis is very much in accordance with the optical and electrical results. The I-V characteristics show a significant enhancement at 500°C, with an improved Ilight/Idark ratio. The barrier height increases with the temperature while decreasing at 500°C due to decreased defects. At 500°C, a least ideality factor of value 1.5 is obtained. If the temperature exceeds 500°C, MnO2 breaks into other oxides like Mn2O3 and Mn3O4. Hence annealing at 500°C is an optimum temperature for better structural, optical, and electrical properties of MnO2 TF, showing great promise for future optoelectronics applications.