摘要

As the crystal materials are applied widely in the fields of aerospace, transportation, electrical and electronic engineering, energy and environmental protection, the new requirements for the researches of their special properties and testing work put forward. Based on the constitutive relationship between the propagation characteristic of acoustic wave in materials and the surface wave velocity, an acoustic elasticity theoretical model of the surface acoustic waves (SAW) velocities of silicon crystal contacting with its elastic constants is established. The theoretical SAW velocities distribution curves of different crystallographic planes versus azimuthal angles are calculated by using the transformation matrix. Experimental measurements of SAW velocities along different azimuthal angles of three crystallographic planes by using the line focusing acoustic transducer, the high-precision defocusing measurement system and V (f, z) analysis, and the experimental curves of SAW velocities are consistent with the theoretical values. It proves that acoustic microscopy (AM) technology is of highly accuracy and reliability for the SAW velocities measurements of anisotropic materials. Meanwhile, the corresponding consistency between the crystal structure and SAW velocities of silicon crystal is studied further, which establishes the theoretical basis for the property detections and evaluations of anisotropic materials including silicon crystal.

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