Electric domains in single-crystal and polycrystalline barium titanate (BaTiO_3) have been observed by use of scanning electron acoustic microscopy (SEAM). A model is presented of the SEAM signal generation, spatial resolution, and contrast mechanism associated with the imaging of electric domains in ferroelectric materials. The SEAM signal is found to depend directly on the sum of the piezoelectric coupling coeffcient and spontaneous polarization of the domain, on the charge density of the electron beam interaction volume, and inversely on both the permittivity and the elastic constants of the material. Application of the model to BaTiO_3 yields a contrast of roughly 3.5 from 90°domain structures and 6.8 from l80 °domain structures.
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