A CWDM with a 20 nm spacing and 8 channels based on AWG is successfully fabricated on 4-inch Si wafer using 0.75%-Δ silica-based waveguides by planar lightwave circuit (PLC) technology. Both simulations and measured results show that broadened pass-band (1 dB bandwidth is above 10 nm)and low crosstalk (no less than 24 dB) are realized by applying a short multimode interference (MMI) structure at the end of input waveguide. The design and fabrication process are introduced, and the simulations and measured results are discussed.