A flexible and stretchable photonic crystal sensor for biosensing and tactile sensing

Abstract A flexible and stretchable photonic crystal that can be used for biosensing and tactile sensing is designed and demonstrated. The nanograting of a flexible and stretchable photonic crystal was fabricated using the nanoreplica molding method with a Si master wafer. The flexible and stretchable photonic crystal consists of PDMS (Polydimethylsiloxane) as the substrate and TiO2 as the high refractive index (RI) layer. The flexible and stretchable photonic crystal was used for strain sensing and biosensing. When the flexible and stretchable photonic crystal was stretched by 0.1%, the peak resonance wavelength shifted 0.4 nm. Also, a refractive index sensitivity of 93 nm/RIU was obtained for biosensing. The proposed flexible and stretchable photonic-crystal-based sensor can be used in the areas of tactile sensing and biosensing in the future.