Layered van der Waals (vdW) ferromagnetic materials, such as ${\mathrm{Cr}}_X{\mathrm{Te}}_Y$ have attracted enormous attention for their exciting electronic and magnetic properties. In this context, this study reports on the manifestations on the Berry curvature effect induced by systematically altering the structural quality and the thickness of the ${\mathrm{Cr}\mathrm{Te}}_2$ (CT) thin films. Of note, these CT films are deposited using dc-magnetron sputtering—a scalable and industrially robust technique, which, to the best of our knowledge, has not been employed previously for ${\mathrm{Cr}\mathrm{Te}}_2$ growth. This distinguishes the film-growth approach adopted in the present work for depositing the CT films from the widely reported molecular beam epitaxy (MBE) and chemical vapor deposition (CVD) routes, which are relatively far less suited for large-scale integration. Two different series of CT films having thickness in 20–60 nm range were deposited on $\mathrm{Si}(100)$ substrates at two different optimized growth temperature of 350 °C and 400 °C, which yielded relatively less crystalline (LC) and highly crystalline (HC) CT films, respectively. Although the Curie temperature ($T_C$) of the LC- and HC-CT films is found to be significantly dependent on their crystalline state, i.e., 140 and 220 K, respectively, a robust perpendicular anisotropy is observed in both the series of CT films (at thickness as high as 20–60 nm), with a high coercivity of 15 and 8 kOe for HC-CT and LC-CT films at 2 K, respectively. Remarkably, the sign of the AHE signal undergoes a change on cooling below 100 K only for the HC-CT films, which is caused by the temperature-dependent change in the Berry curvature. Furthermore, below $T_C$, the longitudinal resistivity of the HC-CT films is predominantly contributed by the electron-magnon scattering contribution as evidenced by its $T^2$ dependence, in sharp contrast to the semiconducting behavior exhibited by the LC-CT films. The sputtered HC-CT films possess superior two-dimentional ferromagnetic characteristics, which are comparable to the films grown via chemical vapor deposition and molecular beam epitaxy techniques.

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• Anomalous Hall effect
• Magnetotransport
• Spintronics
• Ferromagnets
• Magnetic thin films
• Transition metal dichalcogenides
• van der Waals systems
• Sputtering