Two-dimensional (2D) superconductors have intriguing physical properties and abundant potential applications. Recently, 2D superconducting α-Mo₂C and facecentered cubic Mo₂C have been controllably prepared and they bring new viewpoints to carbon-based superconductivity. Although molybdenum carbides (Mo-Cs) have multiple crystalline stacking orders, there are still few structures reported for the lack of higher energy supply during growth. In this study, we report a two-step vapor deposition method to grow superconducting η-Mo₃C₂ films with different thicknesses, with the assistance of controllable plasma power. The grown η-Mo₃C₂ films show polycrystalline characteristics, but they still present superior superconductivity. The 3.0-nm-thick film has the superconducting transition temperature of 5.38 K, and its electrical performances follow truly 2D superconducting transitions. This study will not only exhibit a robust superconducting η-Mo₃C₂ ultrathin film, but also provides a convenient growth way to realize more carbide-based heterostructures for future device applications.

二维（2D）超导体具有令人着迷的物理特性和丰富的潜在应用。最近，2D超导α-沫₂ C和facecentered立方沫₂ c具有被可控地制备，并且它们带来新的视点到基于碳的超导性。尽管碳化钼（Mo-Cs）具有多个晶体堆叠顺序，但据报道仍然很少有结构在生长过程中缺乏较高的能量供应。在这项研究中，我们报告的两步气相沉积法生长超导η钼₃ c ^ _2层膜具有不同厚度的，具有可控等离子体功率的协助。所生长的η-沫₃ Ç ₂薄膜具有多晶特性，但它们仍具有出色的超导性。3.0纳米厚的薄膜具有5.38 K的超导转变温度，其电性能遵循真正的2D超导转变。本研究将不仅表现出强大的超导η钼₃ c ^ ₂超薄膜，还提供了一个方便的生长方式来实现以供将来设备应用多个基于碳化物的异质结构。