High power durability of diamond surface acoustic wave filter

The power durability of the ZnO/diamond surface acoustic wave (SAW) filter was investigated and compared with the LiTaO3 SAW filter. The ZnO/diamond SAW filter maintained linearity of the input-output relation up to the input power of 36 dBm at 2.90 GHz, whereas the LiTaO3 SAW filter, which operated at 822 MHz, was nonlinear above the input power of 23 dBm and degraded significantly at 27.7 dBm. The input power dependence of the time to failure was also investigated for both SAW filters. It was found that the ZnO/diamond SAW filter was durable for 8 dB higher input power than that of the LiTaO3 SAW filter even at 3.5 times higher frequency. These results indicate the extremely high power durability of the ZnO/diamond SAW filter.