Design of a laser writing instrument for selective local patterning of vanadium oxide phases

Vanadium oxides (VOx) are strongly correlated materials that exhibit a variety of collective properties including metal-insulator transitions (MIT). The synthesis of a single-phase vanadium oxide is commonly achieved by controlling thermodynamic conditions. However, synthesizing VOx that combines multiple chemical phases is often challenging since the synthesis conditions for one phase are often destructive to the others. Here, we designed a laser writing instrument that allows for the selective local patterning of high-quality vanadium oxide phases. We combined a laser writing setup with an ultra-high vacuum chamber to implement selective oxide fabrication. We utilized finite element analysis tools to optimize the instrument design and process parameters. Finally, we successfully achieved the controlled synthesis of VO2 , V3O5 and V4O7 embedded in a 100 nm-thick V2O3 thin film matrix. The surface morphology and resistivity of four different vanadium oxide phases were determined experimentally. Our approach offers an alternative pathway for strategically modifying local electronic properties of oxide materials, opening a wide range of potential applications.