High Performance, Biocompatible Dielectric Thin-Film Optical Filters Integrated with Flexible Substrates and Microscale Optoelectronic Devices

Miniaturized, wearable, and implantable optoelectronic devices and systems provide incomparable opportunities for applications in biomedical fields. Optical filters with wavelength selective reflective/transmissive responses that can be integrated onto these biointegrated platforms are critically important for high performance operation. Here, high quality, dielectric thin-film optical filters on unconventional substrates via transfer printing are reported. Designed filters formed on flexible substrates exhibit highly spectral selective transmission and reflection, with the maximum optical density at stop band reaching 6. Additionally, freestanding filter membranes are combined with microscale optoelectronic devices, achieving enhanced emission intensity for light-emitting diodes and spectral sensitivity for photovoltaic detectors. Finally, their in vitro cytotoxicity is evaluated within cell culture, and in vivo biocompatibility is supported in living animals. The presented results offer viable routes to high performance optical components for advanced biointegrated optoelectronic systems.