RESONATEUR HBAR A STABILITE EN TEMPERATURE ELEVEE

The invention relates to a resonator of the harmonic bulk acoustic resonator HBAR type, comprising a piezoelectric transducer (6) clamped between two electrodes (4, 8) with a strong electroacoustic coupling, cut according to a first cutting angle Θ1, and an acoustic substrate (10) with a working frequency acoustic quality coefficient at least equal to 5·1012, cut according to a second cutting angle Θ2 with at least one shearing vibration mode. The transducer and the substrate are arranged in such a way that the polarization direction of the shearing mode of the transducer and the polarization direction of the shearing of the substrate are aligned, and the second cutting angle Θ2 is such that the temperature coefficient of the frequency of the first order CTFB1 corresponding to the shearing mode and to the second cutting angle Θ2 is zero with inversion of the sign thereof on either side of, or equal to, a bias.