Influence of the Magnetron Sputtering Power Source Type on the Formation of TMD Thin Films

High Resolution Image Download MS PowerPoint Slide Transition metal dichalcogenides (TMDs) are promising materials for applications in electronics and optoelectronics due to their tunable electronic properties and atomically thin nature. However, their integration into scalable device fabrication processes still faces significant challenges, particularly with respect to the precise control of the stoichiometry and crystallinity in thin films produced by physical vapor deposition methods. Magnetron sputtering, despite being an industry-standard technique, often results in chalcogen-deficient films, especially when compound targets such as WS 2 are employed. In this work, we investigate the influence of different sputtering power source types (regular DC, RF, and pulsed DC)─on the deposition and subsequent sulfurization of TMD thin films. Pulsed DC and RF sources enable higher chalcogen incorporation and favor the formation of WO 2, which in turn leads to a more efficient sulfurization. The homogeneity and composition of the resulting films are confirmed by multiple techniques. In contrast, regular DC results in poor stoichiometry and film degradation following sulfurization. Our findings highlight the critical role of the sputtering power source type in optimizing TMD thin film formation, providing a viable pathway toward scalable, high-quality deposition processes.