Controlling WSe₂ Synthesis Parameters for Improved Device Performance

Tungsten diselenide (WSe₂), a two-dimensional transition metal dichalcogenide, has attracted widespread research interest due to its direct bandgap and tunable electronic properties. While WSe₂ films can be obtained through mechanical exfoliation of a bulk crystal, other routes of synthesis must be explored to make WSe₂ suitable for industrial use. This work is a systematic exploration of the ambient pressure chemical vapor deposition (CVD) process of WSe₂ synthesis, as it promises higher scalability and comparable electronic performance versus exfoliated samples. We report on the role of seeding promoters and hydrogen in the CVD process, as well as the effects of high-temperature annealing and precursor ratio on overall WSe₂ film quality. The result of our work is high-quality WSe₂ samples suitable for device fabrication or transfer. This work improves the viability for WSe₂ and other transition metal dichalcogenides to be integrated into future nanoelectronics.