Growth of ZrS₂ films with excellent c-axis orientation on h-BN/ SiO₂/Si substrates for optoelectronic application

The integration of two-dimensional transition metal dichalcogenides (TMDs) with Si-platforms offers a pathway to extend Moore's Law and realize advanced optoelectronic devices. ZrS₂, as a typical IVB-group TMD, holds promise for Si-based optoelectronic integration due to its high carrier mobility and current density. However, direct growth of high-quality ZrS₂ films on silicon substrates remains challenging. Herein, we demonstrate that introducing a monolayer hexagonal boron nitride (h-BN) intermediate layer enables the growth of continuous, smooth and dense ZrS₂ films with higher crystalline quality on SiO₂/Si substrates. The ZrS₂ films grown on h-BN/SiO₂/Si exhibit excellent c-axis out-of-plane orientation, achieving a full width at half maximum of 0.72° in the X-ray diffraction rocking curve, significantly lower than the 2.7° for films grown directly on SiO₂/Si. First-principles calculations are performed to understand the different growth behaviors on these two substrates. Photodetectors fabricated from these films exhibit performance metrics on par with those of devices based on exfoliated or epitaxial ZrS₂. This work achieves uniform, large-area growth of high-quality ZrS₂ films on Si-based substrates via an h-BN interlayer strategy, paving the way for integrating ZrS₂ into Si-based optoelectronic devices.