CRYSTALLIZATION BEHAVIOR AND ELECTRICAL PROPERTIES OF INSE AND IN2SE3 THIN FILMS PREPARED BY THERMAL EVAPORATION

Abstract

In recent years, semiconductors based on indium selenide have attracted significant attention in advanced research due to their unique electronic properties. Characteristics such as low effective electron mass, high thermal conductivity, and high photosensitivity are particularly pronounced in two-dimensional (2D) InSe nanocrystals. However, challenges associated with their large-scale fabrication limit their application in industrial technologies. In this work, the crystallization of amorphous In_xSe_y thin films deposited by thermal evaporation is investigated through annealing in an inert gas atmosphere to obtain large-area InSe and In₂Se₃ thin films. It is shown that annealing films with an In/Se stoichiometry of 50/50 at 350 °C leads to the formation of the β­-InSe phase, whereas films with a stoichiometry of 40/60 form a two-phase system consisting of β-In₂Se₃ and γ-In₂Se₃ under the same conditions. The kinetics of electrical resistance during film crystallization is analyzed. Measurements of the temperature dependence of electrical resistance reveal a sharp decrease in the resistance of the InSe film near 170 °C, while the In₂Se₃ film exhibits a two-step decrease at approximately 170 °C and 270 °C. These results demonstrate the potential of these thin-film phase change materials for application in memory devices.