A SAW filter includes a piezoelectric substrate of a single crystal
LiNbO.sub.3 and SAW resonators having an electrode thickness ranging from
about 8% to about 9% of an acoustic wavelength of a high velocity SAW
excited on the surface of the substrate. The piezoelectric substrate has
an orientation defined by Euler angles (.lambda., .mu., .theta.), with
angle .lambda. in a range from -5.degree. to +5.degree., angle .mu. in a
range from about 75.degree. to about 85.degree., and angle .theta. in a
range from 85.degree. to 95.degree.. A metalization ratio for the
resonators ranges from about 0.3 to about 0.9, with resonators in a
parallel arm of the filter having a metalization ratio from 1.1-1.4 times
larger than the metalization ratio for resonators in the series arm of the
filter. Such orientations simultaneously combined with an optimized
electrode thickness and optimized metalization ratios provide an improved
performance in RF applications.
