Dispositivo sensore di gas a struttura fotonica operante mediante onde di superficie di Bloch e relativo procedimento di fabbricazione

A gas-sensing device having a photonic structure, which comprises a multilayer structure (39) made of porous material comprising a periodic multilayer (22; 32) configured for generating Bloch surface waves, and means (23; 33) for directing a light beam (25; 36) incident upon said device (30) towards said multilayer structure (22; 32) in attenuated-total-reflection (ATR) conditions in order to generate said Bloch surface waves, said periodic multilayer (22; 32) comprising a first sensitive face (32e) that is free so as to be exposed to the gas, and a second face (32f) opposite to said first sensitive face (32e). According to the invention, said second face (32f) of said periodic multilayer (32) is set facing said means (33) for directing the incident light beam (36) in ATR conditions, and said multilayer structure (32) made of porous material is fixed to said means (33) for directing the incident light beam (36) in ATR conditions via a bonding layer (34) and a transparent substrate layer (31).