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An experimentally demonstrated, vertical chip-to-chip evanescent coupler between silicon nitride (Si₃N₄) and silicon (Si) is presented with the coupler loss measured to be 0.39 ± 1.06 dB at 1550 nm with a 1-dB bandwidth of 160 nm extending across the C-band, S-band, and L-band (1480-1640 nm). The average coupling loss was determined to be 0.73 dB for the 1480-1640 nm wavelength range with a ± 2σ tolerance of ± 0.92 dB. The 1-dB lateral alignment tolerance was 1.56 ± 0.14 μm at 1550 nm and the average tolerance was 1.38 ± 0.24 μm across the 1480-1640 nm wavelength regime. In addition, the average coupling loss varied by less than ± 0.35 dB and the average 1-dB alignment tolerance varied by less than ± 30 nm for temperatures varying from 23-60°C. Finally, the average coupling loss range was less than 1.5 dB range across four sets of identically packaged die. This is the first experimental demonstration of an inter-chip, passively assembled evanescent coupler using standard CMOS foundry processes for directly coupling between Si and Si₃N₄, overcoming a waveguide refractive index difference of Δn = 1.32 without requiring taper tip widths of less than 100 nm.