Abstract
A RGB-color-mixing device has been studied. To achieve full-range color-mixing and color image generation¸ the use of three basic colors, selectively modulated in three separated intensity modulators, is mandatory. A three-branch optical waveguide, use two Y junction to form a single output is designed and fabricated. The waveguide is fabricated by firstly deposited a 8um thick buffer with TEOS, and then deposited the core layer doped with TMP to modified its index. After deposition and lithography of Cr mask the core layer is then plasma etched. The sidewall roughness and vertical profile of the waveguide are the two key factors for optical performance of the waveguide. We compared the etching characteristic between ICP and RIE and studied the residual stress and the influence of RTA process on the deposited waveguide structure. The fabricated device is tested and shows successfully performing the mixing of light although the loss is still large due to the sidewall roughness resulted from dry etching of the waveguide.