Investigations on the dielectric and ferroelectric characteristics of SBN60 ferroelectric-relaxor thin films on semiconductor substrates in a wide temperature range

Dielectric characteristics, ferroelectric properties, and phase transition temperatures in thin films of ferroelectric-relaxor barium-strontium niobate Sr 0.6Ba0.4Nb2O6 (SBN60) with a tetragonal tungsten bronze structure deposited on a Si(001) semiconductor substrate have been studied by dielectric spectroscopy methods. The films were grown by high-frequency cathode sputtering technique in an oxygen atmosphere. X-ray diffraction analysis has shown that SBN60 films are single-phase, pure and c-oriented (unit cell parameter c = 0.3932 nm), and according to atomic force microscopy, its surface has a uniform relief, does not contain cavities, pores or other surface defects. An approach is proposed which allows determining the permittivity and its dispersion, the temperatures corresponding to interphase transitions. It is based on measuring the high-frequency capacitance-voltage characteristics of the metal/ SBN60/Si(001) capacitor structure at a fixed temperature (in the range 83–473 K). In particular, it is shown that the Burns temperature in the analyzed thin film is 383 K. The applicability of this approach to the metal-ferroelectric-semiconductor heterostructures properties analyses is discussed.

barium-strontium niobate, dielectric characteristics, ferroelectric characteristics, relaxor ferroelectric, thin films, semiconductor substrates, capacitance-voltage characteristics