Polymer-Induced Doping Effect on Indium Selenide

Abstract

Indium selenide (InSe), a promising two-dimensional (2D) material, exhibits various advantageous properties, including low effective mass and near-infrared exciton emission. However, its high surface-to-volume ratio necessitates effective encapsulation to enhance stability and performance. This study examined the impact of poly(methyl methacrylate) (PMMA) encapsulation on the properties of InSe. Raman spectroscopy revealed a blue shift in the vibrational modes of InSe upon PMMA encapsulation, suggesting strain and doping effects. Electrical measurements of InSe-based field-effect transistors indicated a reduction in on-current and a positive shift in threshold voltage, consistent with p-doping and decreased carrier mobility. These findings provide insights into the interaction between 2D materials and encapsulation polymers, emphasizing the role of PMMA in modifying the electrical characteristics of InSe devices. This study contributes to the development of encapsulation strategies to improve the performance and reliability of 2D semiconductor devices.