CMOS-compatible vanadium dioxide via Pulsed Laser and Atomic Layer deposition: towards ultra-thin film phase-change layers

Abstract: Vanadium dioxide, a well-known Mott insulator, is a highly studied electronic material with promising applications in information processing and storage. While fully crystalline layers exhibit exceptional properties, such as a sharp and abrupt conductivity change at the metal-insulator transition, fabricating poly-crystalline films on silicon substrates often involves trade-offs in transport characteristics and switching performance, especially for ultra-thin layers required in advanced gate applications. In this study, we explore the growth of vanadium dioxide films on standard wet-oxidized silicon wafers using two established deposition techniques with pulsed laser deposition and atomic layer deposition. Thin films, ranging in thickness from 200 to 10 nano meters, were systematically characterized through structural and electrical analyses to optimize key growth parameters. Temperature and pressure were identified as the primary factors affecting film quality, and the optimal growth conditions across the entire thickness range are discussed in detail. We demonstrate that both pulsed laser deposition and atomic layer deposition methods can successfully produce ultra-thin vanadium dioxide layers down to 8 nano meters with functional properties suitable for practical applications. This work underscores the potential of vanadium dioxide for fully industry compatible phase-change switching devices and provides valuable insights into optimizing growth processes for poly-crystalline films.