Abstract

During the last decades, great interest has arisen towards the developing of integrated optical devices based on the use of biocompatible materials, which can be used to implement sub-skin implantable and bioresorbable optical sensors. Silk fibroins for example, have shown excellent properties such as transparency in the visible wavelength range and ease of biological functionalization [1], and could be used for the fabrication of optical devices with sub-micrometric dimensions employing an indirect patterning approach. A possible way to in/out couple these optical devices is represented by diffractive grating couplers (GCs): while this approach has already proven to be highly efficient in the Silicon-on-Insulator (SOI) platform [2], its application to sub-skin optical devices is limited by the detrimental effects of light propagation inside the skin, represented by scattering and attenuation.

© 2019 IEEE