Pld Single-phase Magnetoelectric Film Preparation And Its Electrical Properties

This paper to multiferroic materials HoMnO3for the study, using pulsed laser deposition (PLD) grown on different substrates in a HoMnO3film, and an analysis of its structure, growth orientation and the epitaxial relationship with the substrate measured the dielectric constant of the dielectric film changes with frequency, the use of AC impedance spectra of the grain and grain boundaries in the dielectric relaxation of the role of a single measurement of a-axis oriented HoMnO3/Nb-SrTiO3heterogeneous junction IV curve. Details are as follows:Firstly, hexagonal structure HoMnO3were prepared by using high temperature solid state reaction method with a hexagonal structure ceramic material, using X-ray diffraction observed diffraction peaks in addition to HoMnO3, no other impure peaks, indicating that the hexagonal perovskite HoMnO3successful burn target the system.Secondly, Orthorhombic HoMnO3films with a-axis orientations were prepared epitaxially on Nb-1.0wt%-doped SrTiO3single crystal substrates by using pulsed laser deposition technique to fabricate all-oxide heterojunctions. X-ray diffraction and atomic force microscopy were used to characterize the films, and studied with the Nb-SrTiO3substrate epitaxial relationship.Then,temperature dependent the real and imaginary parts of dielectric constant with frequency changes observed in the low-frequency dielectric constant increases with the frequency decreases, there is relaxation peaks, the use of impedance spectroscopy analysis of the film impedance and modulus spectrum, as the temperature changes greatly increase the grain boundary capacitance, capacitance is the same grain size, temperature change on the impact of a large grain boundary resistance. Studied the grain and grain boundary in the role of dielectric relaxation.