In this work, on-chip chalcogenide glass photonic integrations with several fundamental photonic building blocks are designed and fabricated based on the ${\mathrm{As}}_2{\mathrm{S}}_3$ platform for improved 2 μm optical interconnection, achieving a broadened wavelength bandwidth and improved fabrication tolerance. A 600 nm thick ${\mathrm{As}}_2{\mathrm{S}}_3$ strip waveguide has low propagation loss of 1.447 dB/cm at 2 μm. Broadband vertical coupling is realized by a grating coupler with 4.3 dB coupling loss. A Bragg grating filter, power splitter, Mach–Zander interferometer, and mode converter for on-chip mode division multiplexing (MDM) are also reported at 2 μm with reliable performances. Finally, a record high MDM optical interconnection capacity of $3\times 80\mathrm{Gbps}$ at 2 μm is experimentally demonstrated based on the proposed ${\mathrm{As}}_2{\mathrm{S}}_3$ chip, drawing promising prospects for future photonic integration and high-speed interconnection at the 2 μm waveband.