Stanford researchers have developed a novel, inverse-designed wavelength division multiplexer (WDM) that integrates high-performance Bragg gratings for use in optical communication systems. However, limited by the fabrication capability, the deformation in grating teeth typically introduces. In this paper, we propose an ion-exchanged glass waveguide chip to be inserted into the WDM device in order to reduce the output channel spacing. In this paper, a 16-channel WDM device is designed on a Silicon-On-Insulator (SOI) substrate by using a sub-wavelength grating (SWG) structure, which can cover O-band and C-band at the same time, and the.