A PIXELLATED GRATING ARRAY USING PHOTOELECTROCHEMICAL ETCHING ON A GAAS WAVE-GUIDE

We have demonstrated and evaluated a grating array outcoupler fabricat ed by photoelectrochemical (PEC) etching, a manufacturable and practic al approach for fabrication of grating-based II-V semiconductor wavegu ide devices, An array of submicron period gratings was etched into pho tolithographically delineated areas in a single PEC step, The fabricat ed devices are: 10-mu m wide rib waveguides with 0.35-mu m first-order outcoupling gratings; and 10-mu m wide rib waveguides with 10 mu m x 10 mu m pixellated areas of gratings, Device characterization demonstr ates the effectiveness of outcoupling grating fabrication using PEC an d that the pixellated grating outcoupler is an effective and simple me ans of generating an optical beam array.