An ultrasmall 8-channel arrayed waveguide grating (AWG) demultiplexer based on Si nanowire waveguide is designed.The demultiplexer channel spacing is 1.6 nm and its effective area is 420 μm×130 μm.The transimission spectra are simulated by the transimission function method and the results show that the device is with a channel spacing of 1.6 nm and crosstalk of 17 dB.The entire fabrication procedure is given by combining electron beam lithography (EBL) and inductively coupled plasma (ICP) etchin...