Direct Synthesis of Large-Scale Multilayer TaSe₂ on SiO₂/Si Using Ion Beam Technology

The multilayer 1T-TaSe₂ is successfully synthesized by annealing a Se-implanted Ta thin film on the SiO₂/Si substrate. Material analyses confirm the 1T (octahedral) structure and the quasi-2D nature of the prepared TaSe₂. Temperature-dependent resistivity reveals that the multilayer 1T-TaSe₂ obtained by our method undergoes a commensurate charge-density wave (CCDW) transition at around 500 K. This synthesis process has been applied to synthesize MoSe₂ and HfSe₂ and expanded for synthesis of one more transition-metal dichalcogenide (TMD) material. In addition, the main issue of the process, that is, the excess metal capping on the TMD layers, is solved by the reduction of thickness of the as-deposited metal thin film in this work.