Publications by Zian Kighelman

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Relaxor Pb(Mg1/3Nb2/3)O3(PMN) and its solid solutions with ferroelectric PbTiO3 (PT) are of considerable interest from both the applications and the scientific point of view. In the past, many attempts were made to prepare and study the properties of these material in thin film form. However, due to difficulties in the preparation of pure phase films with high PMN content, there exists very little knowledge on the properties of these important materials. It is the goal of this thesis to prepare PMN and PMN-

Pyrochlore free Pb(Mg1/3Nb2/3)O-3 (PMN) thin films were prepared from alkoxide-based solution precursors. The influence of different seeding layers and chemical solution on the microstructures is shown. Dielectric, electrostrictive, and piezoelectric properties of the films were characterized in detail. Films show relaxor-like behavior, but with dielectric permittivity which is low (around 4000 at peak) compared to bulk ceramics and single crystals. Several parameters which might be responsible for this low

Electrode stability, interdiffusion, phase purity and deviation from stoichiometry at the PZT-electrode interface are key issues in PZT thin film integration. This article highlights the use of transmission electron imaging combined with energy dispersive spectroscopy (EDS) for the investigation of these phenomena. The accuracy of the EDS analysis is discussed. It will be shown that using a standard PZT sample and controlled conditions, reliable analysis can be performed. Diffusion mechanisms have been stud

Pyrochlore free 0.9Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) thin films were prepared from alkoxide-based solution precursors. Preferential (111) crystallographic orientation was obtained on TiO2/Pt/TiO2/SiO2/Si substrates by spin coating. Dielectric, electrostrictive, and piezoelectric properties of the films were characterized in detail. Films show relaxor-like behavior, but with dielectric permittivity which is low (around 4300 at peak and at 340 Hz with E-ac=1.6x10(6) V/m) compared to bulk ceramics and single cryst

Pb(Mg1/3Nb2/3)O-3 thin films were prepared from modified alkoxide solution precursors and their dielectric and electromechanical characteristics were investigated. Preparation of the films is very sensitive to processing parameters. The influence of different seeding layers on the microstructures is discussed. Films show relaxer-like behavior, but with dielectric permittivity which is low (4500 at peak) compared to bulk ceramics and single crystals. Large electric de bias fields (up to 120 kV/cm) can be app

PbTiO3 thin films were prepared from alkoxide solution precursors and crystallized onto Pt/TiO2/SiO2/Si substrates. Microscopy observations revealed that the complexity of the domain walls structure decreased with the grain size. Dielectric, electrostrictive, and piezoelectric properties of the films were characterized in details. A shift of the temperature of the dielectric permittivity maximum due to stresses in the plane of films has been observed. Electrostrictive M and Q coefficients were estimated by

Pb(Mg1/3Nb2/3)O-3 (PMN) alkoxide precursor solutions were synthesized and used to prepare thin layers on TiO2/Pt/TiO2/SiO2/Si substrates by spin coating. Many parameters like homogeneity of the solution and appropriate processing must be controlled to minimize the pyrochlore formation. Optimization of the processing allowed highly (111)-oriented thin films to be obtained. Dielectric measurements and TEM investigations were performed and showed that PMN thin films exhibit relaxer behavior.

Pyrochlore free Pb(Mg1/3Nb2/3)O-3 (PMN) thin films were prepared from mixed-metal precursors solutions using the sol-gel process. Lead acetate [Pb(CH3COO)(2)], magnesium acetate [Mg(CH3COO)(2)] and niobium ethoxide [Nb(C2H5O)5] were used as starting materials, while 2-isopropoxy-ethanol was chosen as solvent. The reactivity of the precursors was investigated in order to understand and control the process and thus to prevent the contamination of the PMN with the pyrochlore phase. The solution was spin-coated

The synthesis and molecular structure of a Pb-Mg bimetallic acetatoalkoxide (Pb-6,Mg-12( mu-OAc)(6)(mu(2), eta(2)-OAc)(18)(mu(3), eta(2)-OC2H4OPr1)(12), space group R-3, a = b = 30.032(2), c = 18.855(2) Angstrom, alpha = beta = 90degrees, gamma = 120degrees) are discussed in this article. This compound was isolated as an intermediate during the elaboration of Pb(Mg1/3Nb2/3)O-3 (PMN) using sol-gel process. It results from the reaction of a bimetallic Mg/Nb species with lead acetate in 2-isopropoxyethanol. (C

Pb(Mg1/3Nb2/3)O-3 (PMN) alkoxide precursor solutions were synthesized and used to prepare thin films by spin coating on TiO2/Pt/TiO2/SiO2/Si substrates. Many parameters like the use of homogeneous and stable precursor solutions and appropriate processing were used to greatly reduce the presence of the nonferroelectric pyrochlore phase. Transmission electron microscopy investigations, dielectric, electrostrictive, and direct current field induced piezoelectric measurements were carried out and have shown tha

Zian Kighelman

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Films minces relaxeur-ferroélectriques à base de Pb(Mg1/3NB2/3)O3 : élaboration, propriétés diélectriques et électromécaniques

Electromechanical properties and self-polarization in relaxor Pb(Mg1/3Nb2/3)O-3 thin films

Stoichiometry and interdiffusion in PZT thin films studied by transmission electron microscopy

Dielectric and electromechanical properties of ferroelectric-relaxor 0.9 Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) thin films

Relaxor Pb(Mg1/3Nb2/3)O-3 thin films and their electromechanical properties

Properties of ferroelectric PbTiO3 thin films

Preparation and electromechanical properties of Pb(Mg1/3Nb2/3)O-3 thin film

New sol-gel route for processing of PMN thin films

Insights in the sol-gel processing of Pb(Mg1/3Nb2/3)O-3. The synthesis and crown structure of a new lead magnesium cluster: Pb6Mg12(mu-OAc)(6)( mu(2), eta(2)-OAc)(18)(mu(3), eta(2)-OC2H4OPri)(12)

Relaxor behavior and electromechanical properties of Pb(Mg1/3Nb2/3)O-3 thin films

Electromechanical properties and self polarization in relaxor Pb(Mg1/3Nb2/3)O-3 thin films (vol 89, pg 1393, 2001)