14 years of growth optimization in chemical vapor transport (CVT) as well as flux growth lead to our flawless WS2 crystals: Our large size (~1cm in size) vdW WS2 crystals are treated as gold standards in 2D materials field. Our n-type WS2 crystals are doped with Re or Au atoms at ~1E17-1E18 cm-3 range. WS2 crystals from 2Dsemiconductors are known for its superior valleytronic performance, perfect crystallization, defect free structure, extremely narrow PL bandwidths, clean PL spectra (free of bound exciton shoulders), and high carrier mobility. Thousands of scientific articles have cited us and used these crystals for scientific accuracy and clean signals. Please also see our n- and p-type WS2 crystals doped with Au, Re, Nb, or other transition metal atoms. Please note that doping into TMDCs greatly reduce the crystallization time (growth speeds), thus electronically doped TMDCs measure smaller than undoped (intrinsic) TMDCs.