A scalable molten-salt epitaxy of analog-compatible correlated perovskites at micrometer-scale thickness

Correlated perovskites display extraordinary analog functionalities catering to neuromorphic computing and advanced field perceptions, transcending post-Moore limitations. Nevertheless, it is yet infeasible to achieve scalable material growth of correlated perovskites at micrometer-scale thicknesses, a prerequisite for enabling device resistances compatible with analog circuit requirements. Herein, we demonstrate ultra-effective growth of archetypal metastable correlated perovskites, e.g. nickelates (RENiO₃), via liquid-phase epitaxy within alkali-chloride molten salts, realizing micrometer-scale thickness and scalability. The molten salts provide an ultra-stable thermodynamic environment and consistent ionic-precursor availability for long-period oriented growth, effectively enabling stacking faults formation to mitigate high-magnitude lattice mismatches. This bridges current technological gaps in micrometer-thick film growth of RENiO₃ and achieves record-competitive electronic phase transitions at analog-compatible resistances, enabling more effective and energy-efficient analog cryogenic alarming applications. For the first time, wafer-scale RENiO₃ with high uniformity was successfully grown within low-melting-point eutectic alkali chlorides, eliminating previous reliance on MPa-high oxygen pressures. Our strategy was extendable to multiple oxide systems, covering diverse functionalities, e.g. colossal magnetoresistance, oxide electrodes, and superconductivity.