Monolithically integrated cantilevers with self-aligned tips for wavelength tuning in a photonic crystal cavity-based channel-drop filter

A technology to monolithically integrate micro-bimorph cantilevers equipped with tips that are self-aligned with respect to the holes of a 2D photonic crystal cavity-based channel-drop filter is presented. On electrostatic actuation, the tips move into the holes and provide electromechano-optical modulation of light. The technology allows the fabrication of tips on specific photonic crystal holes by controlling the hole diameter and the sacrificial layer thickness. The integrated device is both mechanically and optically characterized. A 180 pm wavelength shift at the first band edge of the photonic crystal cavity-based channel-drop filter is measured on the application of a 2 V dc voltage to the cantilever. This CMOS-compatible device is designed to operate in the C-band of the telecommunication wavelengths and constitutes a promising candidate for future integrated all-optical devices.