LEAKY SAW PROPAGATION PROPERTIES ON Li2B407 SUBSTRATES

Theoretical and experimental results have shown the potential usefulness of Li2B407 crystals for leaky SAW applications. The existences of orientations with zero TCD have been predicted by the computer analysis and confirmed experimentally for the leaky SAW. Both theoretical and experimental results have shown that the leaky SAW with the zero temperature coefficient of delay (ZTCD) possesses particularly useful cuts such as (h, 90°, 70°), (Oo, 75O, 42') and (0, 75', 75'). The maximum value of k2 exists at 9 of around 60' to 70' on the (h, 90°, 9). k2 of the Rayleigh wave is zero at (h, 90'. 70°), which gives no spurious response for the leaky SAW. Temperature-compensated leaky SAW orientations have been located at both the (0, 75', 75') and (45'. 90'. 70') with vp of 4225 and 3680 mJs and k2 of 1.8 and 2.3%, respectively. Further it has been confirmed theoretically and experimentally that a longitudinal leaky SAW with the fast velocity of 6825ds also exists around (Oo, 45', 90').