Abstract
The present invention relates to a waveguide coupler capable of two-step coupling and a manufacture method thereof, the waveguide coupler comprises: a substrate, at least one waveguide layer, at least one assisting grating, at least one coupling material layer, and at least one 3-D structure layer, wherein it is able to couple the light into the waveguide layer by way of two-step coupling through the 3-D structure layer, the coupling material layer and the assisting grating. The manufacture method is adapted to fabricate the waveguide coupler capable of two-step coupling via the present semiconductor process technology without increasing any equipment.