Si-CMOS Compatible Synthesis of Wafer-Scale 1T-CrTe2 with Step-Like Magnetic Transition

Abstract

2D room-temperature ferromagnet CrTe₂ is a promising candidate material for spintronic applications. However, its large-scale and cost-effective synthesis remains a challenge. Here, the fine controllable synthesis of wafer-scale 1T-CrTe₂ films is reported on a SiO₂/Si substrate using plasma-enhanced chemical vapor deposition at temperatures below 400 °C. Magnetic hysteresis measurements reveal that the synthesized 1T-CrTe₂ films exhibit perpendicular magnetic anisotropy along with distinct step-like magnetic transitions. It is found that 1T-CrTe₂ is susceptible to oxygen adsorption even in ambient conditions. The theoretical calculations indicate that the oxidation of surface layers is crucial for the absence of out-of-plane easy axis in few-layer CrTe₂, while the interlayer antiferromagnetic coupling among the upper surface layers leads to the observed step-like magnetic transitions. The study provides a Si-CMOS compatible approach for the fabrication of magnetic 2D materials and highlights how unintentional adsorbents or dopants can significantly influence the magnetic behaviors of these materials.