Abstract
A thin ScAlN layer was deposited on high resistivity (111) oriented
silicon and two port surface acoustic wave (SAW) devices were
manufactured, using advanced nanolithographic techniques, on this
material. The Surface Acoustic Wave and Spin Wave (SAW/SW) coupling was
performed via a thin ferromagnetic layer (Ni) placed between the
interdigitated transducers (IDTs) of the SAW device. Since the phase
velocity in this material is lower than in the Si substrate, both
Rayleigh (4.67 GHz) and Sezawa (8.05 GHz) propagation modes could be
observed. The amplitude of the S21 parameter around the
two resonances was measured for values of the magnetic field
µ0H from -280 to +280 mT, at different angles (θ)
between the SAW propagation direction and the magnetic field direction.
A maximum decrease of 2.54 dB occurred in S21 for the
Rayleigh mode at µ0H = -90 mT, and of 7.24 dB for the
Sezawa mode at µ0H =-203 mT, both at θ = 45°. These
values were extracted from time gated processing of the frequency domain
raw data.