SURFACE AND DOMAIN-STRUCTURES OF FERROELECTRIC-CRYSTALS STUDIED WITH SCANNING FORCE MICROSCOPY

The understanding of the phenomena of ferroelectricity requires profou nd knowledge of the ferroelectric domain structure. In this paper we r eport on the progress of studying ferroelectric domains and domain wal ls with scanning force microscopy (SFM). Domains and domain walls of f erroelectric crystals of guanidinium aluminum sulfate hexahydrate (GAS H) are imaged with SFM. Two sets of complementary results are obtained depending on the operation mode of the instrument. In the non-contact imaging mode (attractive force regime), domain walls are imaged. In t he contact imaging mode (repulsive force regime) in addition to the do main wall structure, information about the polarity of the domains is obtained. In these latter images, the opposing contrast of the ferroel ectric positive and negative domains is superimposed on the GASH cleav age structure. The imaging mechanism of the contact and noncontact mod es are discussed. Corroborating scanning electron microscopy images ar e presented as well.