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van der Waals (vdW) heterostructures are promising building blocks for future ultrathin electronics. Fabricating vdW heterostructures by stamping monolayers at arbitrary angles provides an additional range of flexibility to tailor the resulting properties than could be expected by direct growth. Here, we report fabrication and comprehensive characterizations of WSe₂/WS₂ bilayer heterojunctions with various twist angles that were synthesized by artificially stacking monolayers of WS₂ and WSe₂ grown by chemical vapor deposition. After annealing the WSe₂/WS₂ bilayers, Raman spectroscopy reveals interlayer coupling with the appearance of a mode at 309.4 cm^–1 that is sensitive to the number of WSe₂ layers. This interlayer coupling is associated with substantial quenching of the intralayer photoluminescence. In addition, microabsorption spectroscopy of WSe₂/WS₂ bilayers revealed spectral broadening and shifts …