ZnO

LiNbO₃

AlN

Aluminum

173.5 Hz, 8.20 V

187.5 Hz, 1.67 V

279.5 Hz, 3.80 V

Steel

170.0 Hz, 9.82 V

183.5 Hz, 1.49 V

272.0 Hz, 4.86 V

Silicon

175.0 Hz, 5.19 V

189.0 Hz, 1.00 V

281.0 Hz, 4.4 V