In this study we are interested in the implementation of mixed processes for the realization of symmetrical structures shaped in thin layers for integrated photonics and based on silicon plus organic UV210. We used the so called UV210 polymer for shaping the core waveguide. The UV210 polymer made up of poly (p-hydroxystyrene) and poly (t-butyl acrylate) is a chemically amplified resin; a photo-acid generator is added to the matrix of the copolymer in order to increase the sensitivity of the resin and create a chain reaction during developments so as to develop sub-wavelength patterns. Several families of multilayers structures have been produced by specific sub-wavelength lithography plus PECVD, and then properly characterized by including stoichiometry analyses plus imaging by Raman. The advantage of achieving Si/SiO2/UV210/Si/SiO2 symmetry relates first of all to the equations of electromagnetism and guidance which no longer impose a cut-off thickness (or frequency) during extreme miniaturization, but also for an adequate protection of the components by an upper layer of silicon covering the surface of the chip for sensor applications and specific detection of aggressive substances / agents. All structures, including the addition of silicon directly onto the organic, exhibit excellent mechanical strength and optical stability; the last silicon/silica bilayer also acts as a thin protective shell. Various families of resonant photonic structures could be cleanly characterized on platform. Furthermore, by statistical measurements of resonance parameters, we conclude that the processes and properties of the materials obtained have good reproducibility. This opens the way to the realization of sensors dedicated to aggressive substances directly in contact with the resonant elements probing it.