Rhombohedral-stacked transition metal dichalcogenides (TMDs) break inversion symmetry between adjacent layers, giving rise to an intrinsic out-of-plane ferroelectric polarization. Controlling the formation of this stacking polytype is therefore essential for harnessing ferroelectric effects in two-dimensional materials. In this work, we demonstrate the epitaxial growth of rhombohedral bilayer tungsten diselenide (3R-${\mathrm{WSe}}_2$) on a cubic W(110) single crystal by molecular beam epitaxy. We show that selenium passivation of the substrate is key to enable a quasi-van der Waals epitaxy, effectively suppressing strong interfacial bonding and promoting the growth of quasi free-standing bilayer films. The 3R stacking order is confirmed through a combination of Raman spectroscopy and high-resolution angle-resolved photoemission spectroscopy (ARPES), supported by density functional theory (DFT) calculations. ARPES and DFT reveals an indirect-gap electronic structure with the valence-band maximum at the Γ point, as well as a pronounced spin-orbit-driven splitting of $520\pm 20$ meV at the K point. Analysis of the measured dispersions yields hole effective masses of $0.46\pm 0.04m_e$ and $0.75\pm 0.06m_e$ for the upper and lower valence bands at K point, respectively. These results establish a robust route for synthesizing quasi-free-standing 3R-${\mathrm{WSe}}_2$ and provide a platform for exploring the electronic, optical, and ferroelectric functionalities that emerge from inversion-symmetry breaking in layered TMDs. Our findings further highlight the potential of cubic substrates for deterministic fabrication of rhombohedral TMD heterostructures and ferroelectric devices at the nanoscale.

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• Electrical properties
• Bilayer films
• Transition metal dichalcogenides
• Two-dimensional electron system
• Molecular beam epitaxy