Extended Data Fig. 10: Raman spectra of monolayer MoS₂ under different fabrication processes.

a, Raman spectra of initial MoS₂, after vdW laminated CPVA, after spin-coated CPVA, and after plasma etching (MoS₂ with CPVA protection) at 150 W for 20 min. b, c, \({{\rm{E}}}_{2{\rm{g}}}^{1}\) and A_1g Raman position (b) and full width at half maxima (c) of monolayer MoS₂ under different fabrication processes. After laminating interlayer dielectric CPVA, the \({{\rm{E}}}_{2{\rm{g}}}^{1}\) Raman position and its peak FWHM remain unchanged, suggesting the minimized defects or strain during the lamination process. In contrast, by directly spin-coating CPVA on top of MoS₂ surface, \({{\rm{E}}}_{2{\rm{g}}}^{1}\) peak blue-shifts by 0.9 cm⁻¹ and its FWHM increases by 0.6 cm⁻¹, indicating the generation of additional defects or strains during the solution-based coating processes. Similarly, the \({{\rm{E}}}_{2{\rm{g}}}^{1}\) peak exhibits large shifts of 2.0 cm⁻¹ with FWHM increases of 1.2 cm⁻¹ after plasma process, indicating the MoS₂ delicate lattice could still be impacted by the plasma process, even covered by 700 nm thick CPAV layer.