Several types of piezoelectric materials used in SH-SAW sensors and their advantages.

Materials	Orientation	Frequency range (MHz)	Coupling coefficient, K2 (%)	Dielectric constant	TCF [ppm per °C]	Advantage	Reference
36° YX LiTaO3	x-axis	100–150	5–6.6	43	32	Reduces the TCF, label-free detection, minimal energy loss, low signal loss, reproducibility	84 and 85
64° YX LiNbO3	x-axis	∼100 to ∼450	46.4	85.2	∼80	Low cost, low power consumption, wide application, suitable for fluid loading	86 and 87
36° YX LiNbO3
Quartz	z-axis	134–570	0.1–0.2	3.8	0	High sensitivity and temperature stability, low insertion loss	82 and 84
ZnO	c-axis	153	1.5–1.7	8.66	∼−60	Best microfluidic performance, simple operation, precision, low cost, fast response, and reduced reagent requirements	82, 85 and 88
All		520	3.1–8	8.5	19