Fabrication of a 3GHz oscillator based on Nano-Carbon-Diamond-film-based guided wave resonators

International audience; We have investigated the possibility to use carbon-diamond layers exhibiting nano-sized grains for the fabrication of SAW resonators. One of the main purpose was to check the influence of the grain size on the resonator's spectral signature and to evaluate the fabrication of high frequency sources along this approach. We have investigated various material combinations on Nano-Carbon-Diamond (NCD) layers grown along different techniques (nano-seeding, BEN, followed by MPCVD). The best configuration was based on ZnO/NCD material combination provided the piezoelectric layer was deposited on the so-called nucleation surface of the NCD. Numerous resonators have been fabricated on such substrates, allowing to characterize and exploit the resonance near 3 GHz. An oscillator then was built using such a configuration: its stability has been measured near 10-7 and its phase noise was found near −100 dBc.Hz-1 at 10 kHz.