UHF acoustic attenuation and quality parameter limits in the diamond based HBAR

Abstract

Ultra high frequency attenuation limits in synthetic IIa diamond single crystal were studied. The investigations were provided by High-overtone Bulk Acoustic Resonator "Al/AlN/Mo/(100) diamond". It was shown, that the change of Akhiezer's attenuation regime to Landau-Rumer one takes place at f ª 1 GHz. The experimental results on the quality parameter showed Q¥f ª 1.8◊10 13 Hz for Akhiezer's regime, and Q¥f ª f¥1.8◊10 4 Hz for Landau-Rumer regime. As a consequence on a higher frequencies diamond single crystal has more preferred acoustic parameters including a lower acoustic attenuation in comparison with known acoustoelectronic materials.

Resonant transformation of acoustic waves observed for the diamond based HBAR

“…It was supposed that the acoustic attenuation for Al, AlN, and Mo obeyed to the Akhieser's law: α ~ f 2 at all the frequencies, but, starting from ~ 1 GHz the acoustic attenuation for single crystalline diamond should be changed as α ~ f. The last is defined by the transition to Landau-Rumer regime as was shown in our paper [13].…”