Self‐Saturated Deposition and Etching in Atomic‐Scale (SDEA) Process of Molybdenum Oxides via Sequential Ozone and Water Reactions

Abstract Molybdenum dioxide (MoO 2 ) has attracted significant attention as a high‐work‐function electrode material for next‐generation metal‐insulator‐metal (MIM) capacitors, particularly for stabilizing the rutile phase of TiO 2 with a dielectric constant of 150. However, challenges such as stoichiometric variations in high‐aspect‐ratio structures and morphology degradation during reduction have limited its practical applications. To address these issues, a novel self‐limiting deposition and etching in atomic‐scale (SDEA) process is introduced. This approach combines atomic layer deposition (ALD) of MoO a (2 < a < 3) using Mo + O 3 , followed by atomic layer etching (ALE) of MoO 3 using H 2 O. The process selectively removes MoO 3 through etching, leveraging the self‐limiting nature of both reactions to achieve precise atomic‐scale control over oxidation states without morphology degradation. MoO 2 films deposited using this method exhibit enhanced electrical performance, including a higher dielectric constant and reduced leakage current when employed as bottom electrodes in TiO 2 ‐base metal‐insulator‐metal capacitors. This work provides a transformative solution for integrating MoO 2 into cutting‐edge semiconductor devices, overcoming the limitations of existing deposition techniques. The SDEA process represents a significant advancement in material and process engineering, offering new possibilities for device miniaturization and performance enhancement.