Abstract: As a key candidate material for integrated circuits in the post-Moore era, wafer-scale high-quality preparation of two-dimensional molybdenum disulfide (MoS₂) is fundamental for its industrial application. While chemical vapor deposition (CVD) on sapphire substrates enables large-area MoS₂ film growth, it is constrained by non-uniform molybdenum source deposition resulting from weak adsorption of gaseous MoO₃ at the Al-O interface, leading to film wrinkling and crack defects. This study proposes a growth strategy employing an Al-O-Mo-O chemical bonding modification layer on the substrate surface, successfully fabricating a uniform, continuous, and high-coverage 2-inch wafer-scale monolayer MoS₂ film. By maintaining a stable oxygen atmosphere during the pre-annealing deposition step, this method simultaneously eliminates dangling bonds on the sapphire surface and constructs an Al-O-Mo-O modification layer. This layer provides stable anchoring sites for gaseous MoO₃ deposition, enhancing its adsorption at the interface and promoting uniform adsorption, deposition, and sulfurization of the molybdenum precursor across the substrate. Consequently, a high-coverage monolayer MoS₂ film is achieved. Top-gated transistor arrays fabricated from this film exhibit excellent performance uniformity, with a maximum on/off ratio of 10⁷, a maximum on-state current of 10⁻⁵ A, and a device yield exceeding 96%. The substrate modification method presented in this work provides a novel approach for the controllable preparation of high-quality MoS₂ films on sapphire, optimizes existing fabrication processes, and holds significant promise for advancing the application of two-dimensional materials in integrated circuits.