Premium
Ferroelectric domains and material contrast down to a 5 nm lateral resolution on uniaxial ferroelectric triglycine sulphate crystals
Author(s) -
Eng L. M.,
Bammerlin M.,
Loppacher Ch.,
Guggisberg M.,
Bennewitz R.,
Meyer E.,
Güntherodt H.J.
Publication year - 1999
Publication title -
surface and interface analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.52
H-Index - 90
eISSN - 1096-9918
pISSN - 0142-2421
DOI - 10.1002/(sici)1096-9918(199905/06)27:5/6<422::aid-sia534>3.0.co;2-2
Subject(s) - ferroelectricity , piezoresponse force microscopy , antiparallel (mathematics) , polarization (electrochemistry) , amplitude , condensed matter physics , materials science , triglycine sulfate , chemistry , optics , dielectric , optoelectronics , physics , magnetic field , quantum mechanics
We operate dynamic force microscopy (DFM) innon‐contact mode under ultrahigh vacuum conditions in order todifferentiate local chemical inhomogeneities from ferroelectricdomains in bulk single crystals of triglycine sulphate(TGS). Individual layers of both mixed glycine andsulphate, and pure glycine ions are resolved resulting in a lateralmaterial contrast of 5 nm and a sub‐unit cell verticalcontrast. The clue information is deduced when analysing theexcitation amplitude A exc applied to the piezoshaker in constant amplitude DFM which is strongly affected either bythe short‐range chemical force or the longer rangeelectrostatic contribution. The latter arises from the bound surfacecharge within individual ferroelectric domains and results in along‐range tip–sample interaction. From variation of thebias voltage applied to the TGS counter electrode we deduce the signof the bound surface charge within each ferroelectric domain. Hence,domain walls that separate regions of antiparallel polarization areresolved down to a 9 nm domain wall width. Copyright © 1999 JohnWiley & Sons, Ltd.