<p>In this study, Indium selenide thin films were fabricated by magnetron sputtering and systematically investigated as a function of post-deposition annealing temperature. Structural analysis reveals that the as-grown films predominantly crystallize in a poorly ordered In₂Se₃ phase. With increasing annealing temperature, a pronounced phase transition from In₂Se₃ to layered InSe is observed, accompanied by a significant improvement in crystallinity and the emergence of highly textured InSe (00&#xa0;l) orientations. Surface morphology evolves concurrently from a granular structure toward a more uniform and dense film, indicating enhanced atomic rearrangement during annealing. Electrical transport measurements demonstrate that the phase transition strongly affects the conduction behavior, leading to marked changes in resistivity with annealing temperature. In addition, photoluminescence spectroscopy exhibits a clear energy shift from the characteristic emission of In₂Se₃ to that of InSe, providing optical confirmation of the structural transformation. These results highlight post-deposition annealing temperature as a key parameter for controlling the phase, crystal structure, and optoelectronic properties of sputtered indium selenide thin films.</p>