Pedestal height influence on AlN pedestal-type optical waveguides

In this work, Aluminum Nitride (AIN) pedestal-type optical waveguides were fabricated and characterized. For the fabrication of these devices, a 0.6 μm-thick AIN film and a 1.5 μm-thick thermally grown silicon dioxide (SiO₂) film were used as core and cladding layer, respectively. AlN films were deposited by RF reactive magnetron sputtering using parameter conditions studied previously. The pedestal profile was defined using conventional photolithography, followed by plasma etching of the cladding layer. The pedestal height was varied in 0.6, 1 and 1.2 μm. Optical losses characterization were measured in these devices using the top-view technique at a wavelength of 633 nm for all three pedestal heights and with widths varying from 1 to 100 μm.