The demand for compact and autonomous systems devoted to field detection of gaseous compounds is still persisting in a rapidly changing international context (food-processing, sustainable development, security, and so on). The thesis reported in this manuscript, supported by the Délégation Générale de l'Armement, develops new resonant sensor solutions based on high overtone bulk acoustic waves (so-called HBARs) for chemical compound detection and more specifically explosive substances. These high compactness resonators are built using a transducer bound or deposited onto a resonant cavity, yielding a comb spectrum modulating its own frequency response. They are used generally as dipoles, but a quadrupole structure allowing for transverse mode coupling has been particularly used for our developments. A theoretical study of the behaviour of these devices based on lithium niobate-on-quartz or qluminum nitride-on-silicon material stack has been achieved to determine the gravimetric properties of these configurations accounting for their mode specificities. Various calibration techniques have been implemented to confirm the theoretical analysis and to define the most appropriate structure for a given application. The produced results have been compared to those of a quartz guided-wave micro-balance to emphasize the strength (compactness, reduced chemical kinetics, multiphysics measurements) and weakness (gravimetric sensitivity requiring device thickness less than 100 μm) of our devices. An embedded signal processing electronics also has been developed to treat the information provided by our sensors, offering fast or accurate (millidegree range) detection protocols. The dedicated electronics aims at providing the flexibility needed to track multiple modes at variaous fixed frquencies while getting rid of the long sweep time of general purpose network analyzers. A eight-channel version of this system has been set to process several sensor in parallel or to monitor several modes of two HBAR sensors for effective muti-physics measurements in a reduced analysis domain (a few cubic mm). Phase noise is the limiting factor determining the detection limit. The system has been deployed for gas detection as well as for monitoring other physical parameters such as temperature or viscosity under various experimental condition including fluid media.
