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 degrees 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 degrees C, with an improved I-light/I-dark ratio. The barrier height increases with the temperature while decreasing at 500 degrees C due to decreased defects. At 500 degrees C, a least ideality factor of value 1.5 is obtained. If the temperature exceeds 500 degrees C, MnO2 breaks into other oxides like Mn2O3 and Mn3O4. Hence annealing at 500 degrees C is an optimum temperature for better structural, optical, and electrical properties of MnO2 TF, showing great promise for future optoelectronics applications.