We measure the phase velocities of surface
acoustic waves (SAWs) propagating at different crystal orientations on
(001)-cut GaAs substrates and their temperature dependance. We design and
fabricate sets of interdigital transducers (IDTs) to induce 4 μm SAWs via the
inverse piezoelectric (PZE) effect between the PZE [110] direction (set as θ =
0°) and the non-PZE [100] direction (θ = 45°) on GaAs. We also prepare ZnO film
sputtered GaAs substrates in order to launch SAWs efficiently by IDTs even in
the non-PZE direction. We quantify acoustic velocities between 1.4 and 300 K
from the resonant frequencies in the S 11 parameter using a network analyzer.
We observe parabolic velocity–temperature trends at all θ-values both on GaAs
and ZnO/GaAs substrates. Below 200 K, in ZnO/GaAs substrates slower SAW modes
appear around the [110] direction, which are unseen at RT.
Source:IOPscience
For more information, please visit our website: www.semiconductorwafers.net,
send us email at sales@powerwaywafer.com and powerwaymaterial@gmail.com
No comments:
Post a Comment