Phase transition and switching behavior in thermally evaporated In₂Se₃ thin films for memory applications

Indium selenide (In₂Se₃), a binary chalcogenide, crystallizes in multiple phases and has got significant interest for its ability to transition between amorphous and crystalline states. Defects such as vacancies play a crucial role in shaping its structural and electrical properties, making it a promising candidate for phase change memory (PCM) applications. In this study, In₂Se₃ thin films were deposited on glass substrates using the thermal evaporation technique. The as-deposited films were initially amorphous and transformed into γ-In₂Se₃ upon annealing, leading to notable changes in its optical and electrical properties. Since phase transition is a key characteristic of phase change materials, temperature-dependent XRD and Raman spectroscopy were conducted to determine the transition temperature. To further validate these findings, temperature-dependent resistance measurements were performed. The γ-In₂Se₃ films exhibited high crystallization temperatures, and their switching behavior was successfully demonstrated with a threshold electric field 3.6×10⁶V/m and holding field of 2.4×10⁶V/m