OPTICAL WAVEGUIDE FABRICATION METHOD

摘要

The present invention relates to a method of manufacturing optical waveguide devices. The order of patterning/etch in the method is first a deeper etching then shallow etching. In some embodiments, the first etching forms a mesa and the second etching removes a portion of material that comprises the mesa. In addition, there can be a planarization step. The deeper trenches are desirably conducive to filling. The method may use a cross-lithography method to reduce alignment errors between multiple patterning/etching steps. The method may use an oxidation and stripping off process to smooth a surface of the waveguide and/or reduce an initial dimension of the waveguide.