Microstructural Changes During Processing of Laser-Deposited BaTiO3 and Pzt Thin Films

1990 ◽  
Vol 202 ◽  
Author(s):  
L. P. Cook ◽  
M. D. Vaudin ◽  
P. K. Schenck ◽  
W. Wong-Ng ◽  
C. K. Chiang ◽  
...  

ABSTRACTThin films of BaTiO3 and PZT (lead zirconate titanate, 47%PbTiO3, 53%PbZrO3) have been produced by laser irradiation of the appropriate ceramic targets and deposition of the ejected and vaporized material on planar substrates. The microstructural changes during thermal processing of these films have been studied by scanning electron microscopy/energy dispersive x-ray spectrometry (SEM/EDX), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), x-ray diffraction (XRD), and by measurement of electrical properties. Films have been deposited using both Nd/YAG and excimer lasers and on unheated as well as heated substrates. Excimer films are considerably smoother than the Nd/YAG films, and the uniformity of the as-deposited microstructures is promoted by substrate heating. However, ferroelectric hysteresis loops were only observed for the considerably less smooth Nd/YAG PZT films; thermal treatment did little to improve the smoothness of these films. An excimer BaTiO3 film deposited on a heated substrate showed crystallographic alignment and had a dielectric constant of −100. Efforts are underway to combine the best features of films produced by both methods.

1991 ◽  
Vol 230 ◽  
Author(s):  
A. Pignolet ◽  
P. E. Schmid ◽  
L. Wang ◽  
F. Lévy

AbstractPure and doped lead-titanate (PT) and lead-zirconate-titanate (PZT) thin films have been deposited on platinum-coated silicon by rf-magnetron sputtering from pressed powder targets. The films have been deposited without substrate heating. The amorphous films were then annealed in an oxygen flow. The structure of the films is tetragonal or rhombohedral depending on composition. The electrical resistivity, dielectric permittivity, ferroelectric hysteresis and pyroelectric coefficient are reported.


2007 ◽  
Vol 14 (02) ◽  
pp. 229-234
Author(s):  
SARAWUT THOUNTOM ◽  
MANOCH NAKSATA ◽  
KENNETH MACKENZIE ◽  
TAWEE TUNKASIRI

Lead zirconate titanate (PZT) films with compositions near the morphotropic phase boundary were fabricated on Pt (111)/ Ti / SiO 2/ Si (100) using the triol sol–gel method. The effect of the pre-heating temperature on the phase transformations, microstructures, electrical properties, and ferroelectric properties of the PZT thin films was investigated. Randomly oriented PZT thin films pre-heated at 400°C for 10 min and annealed at 600°C for 30 min showed well-defined ferroelectric hysteresis loops with a remnant polarization of 26.57 μC/cm2 and a coercive field of 115.42 kV/cm. The dielectric constant and dielectric loss of the PZT films were 621 and 0.0395, respectively. The microstructures of the thin films are dense, crack-free, and homogeneous with fine grains about 15–20 nm in size.


2006 ◽  
Vol 20 (21) ◽  
pp. 3071-3080 ◽  
Author(s):  
N. UDOMKAN ◽  
P. LIMSUWAN ◽  
P. WINOTAI ◽  
T. TUNKASIRI

The purpose of this research is to investigate the structure of lead zirconate titanate ceramics ( Zr:Ti =52:48) when doped with Pr2O3and the corresponding properties such as micro-structural properties, physical properties, dielectric constant (εr), piezoelectric properties (kp, Qm, and d33), and the ferroelectric property. The materials were prepared via conventional mixed oxide method and sintered at 1200°C. The Rietveld refinement of X-ray diffraction patterns and combination of both patterns revealed the tetragonal structure for all samples to have space group of P4mm. For higher dopant content (10 mol%), the pyrochlore phase of Pr2O3also appeared in the respective samples. These pyrochlore phases caused the detriment of dielectric and piezoelectric properties. For those with lower dopant content (1.00 mol%), the Pr ion substituted at the A and B sites with isovalent dopant effects, i.e. a lower value of εr, and kp. The hysteresis loops indicated the ferroelectric property for all samples. The microstructure showed dense grain according to a high density and the additional phases of Pr2O3were clearly observed for 10 mol% doping. The Curie temperature decreased with increasing dopant content, as determined from high temperature X-ray diffraction and differential scanning calorimetry.


1991 ◽  
Vol 230 ◽  
Author(s):  
C. K. Chiang ◽  
W. Wong-Ng ◽  
P. K. Schenck ◽  
L. P. Cook ◽  
M. D. Vaudin ◽  
...  

AbstractDense smooth lead zirconate-titanate thin films have been prepared by excimer laser deposition. The as-deposited films are amorphous as indicated by x-ray powder patterns. Differential scanning calorimetry studies show that the film has a glass transition at 301 °C, and the amorphous to crystalline transformation takes place above 350°C to 650°C. Phase formation as a result of post-deposition heat treatment is described.


2005 ◽  
Vol 19 (10) ◽  
pp. 1757-1769 ◽  
Author(s):  
P. SRIMAUNGSONG ◽  
N. UDOMKAN ◽  
L. PDUNGSAP ◽  
P. WINOTAI

The purpose of this research is to investigate the structure of lead zirconate titanate ceramics (Zr:Ti = 52:48) doped with CeO2and corresponding properties such as micro-structural properties, physical properties, dielectric constant (εr), piezoelectric properties (kp, Qm, and d33), and the ferroelectric property. The specimens were prepared via a conventional mixed oxide method and sintered at 1200°C. Rietveld refinement of X-ray diffraction patterns resulted in the P4mm tetragonal structure for all samples. At a high dopant content (10 mol%), pyrochlore phases of CeO2appeared which caused the detriment of dielectric and piezoelectric properties. At a low dopant content (1 mol%), Ce4+ions entered the B site with isovalent dopant effects, and clearly resulted lower values of εr, and kpcompared with those of the undoped sample. The hysteresis loops showed ferroelectric properties for all samples. Microstructures displayed dense grain distribution and thus yielded a high density. The additional phase of CeO2was clearly observed for 10 mol% doping which implied it was overdoped. Finally, the Curie temperature has been found to decrease with increasing dopant content, as determined from high temperature X-ray diffraction and differential scanning calorimetry.


1997 ◽  
Vol 12 (4) ◽  
pp. 1043-1047 ◽  
Author(s):  
Chang Jung Kim ◽  
Dae Sung Yoon ◽  
Joon Sung Lee ◽  
Chaun Gi Choi ◽  
Kwangsoo No

The lead zirconate titanate (PZT) thin films were fabricated using sol-gel spin coating onto Pt/Ti/glass substrates. Effects of the holding time for pyrolysis and the coating cycle on the preferred orientation of the PZT thin films were studied. The films were fabricated with different coating cycles (3, 5, 7, 9, 11), dried at 330 °C for different holding times (5, 30, 60 min), and then annealed at the same temperature of 650 °C using rapid thermal annealing (RTA). The preferred orientations of the films were investigated using x-ray diffraction and glancing angle x-ray diffraction. The microstructure and the selected area diffraction pattern of the PZT thin films were also investigated using scanning electron microscopy (SEM) and transmission electron microscopy (TEM), respectively.


2021 ◽  
Vol 6 (1) ◽  
pp. 27
Author(s):  
Clemens Mart ◽  
Malte Czernohorsky ◽  
Kati Kühnel ◽  
Wenke Weinreich

Pyroelectric infrared sensors are often based on lead-containing materials, which are harmful to the environment and subject to governmental restrictions. Ferroelectric Hf1−xZrxO2 thin films offer an environmentally friendly alternative. Additionally, CMOS integration allows for integrated sensor circuits, enabling scalable and cost-effective applications. In this work, we demonstrate the deposition of pyroelectric thin films on area-enhanced structured substrates via thermal atomic layer deposition. Scanning electron microscopy indicates a conformal deposition of the pyroelectric film in the holes with a diameter of 500 nm and a depth of 8 μm. By using TiN electrodes and photolithography, capacitor structures are formed, which are contacted via the electrically conductive substrate. Ferroelectric hysteresis measurements indicate a sizable remanent polarization of up to 331 μC cm−2, which corresponds to an area increase of up to 15 by the nanostructured substrate. For pyroelectric analysis, a sinusoidal temperature oscillation is applied to the sample. Simultaneously, the pyroelectric current is monitored. By assessing the phase of the measured current profile, the pyroelectric origin of the signal is confirmed. The devices show sizable pyroelectric coefficients of −475 μC m−2 K−1, which is larger than that of lead zirconate titanate (PZT). Based on the experimental evidence, we propose Hf1−xZrxO2 as a promising material for future pyroelectric applications.


2021 ◽  
Vol 8 (3) ◽  
pp. 14-19
Author(s):  
Thuy Nguyen Thanh ◽  
Tung Nguyen Van ◽  
Hung Nguyen Trong ◽  
Minh Cao Duy

Lanthanum-doped lead zirconate titanate (PLZT) powders were synthesized using thehydrothermal method. The influence of pH, reaction temperature and time, lanthanum concentration on the formation and characteristics of PLZT were investigated. Obtained powders were investigated using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) techniques and a dielectric analyzer. The results showed that           Pb1-xLax(Zr0.65Ti0.35)O3 with x= 0.0 – 0.1 were well formed under conditions: pH≥13, reaction time of 12hrs, reaction temperature of 180oC. Dielectric constant of PLZT is higher than PZT. The grain size of the PLZT is found to be 1–3.5 µm.


1990 ◽  
Vol 200 ◽  
Author(s):  
C. K. Chiang ◽  
L. P. Cook ◽  
P. K. Schenck ◽  
P. S. Brody ◽  
J. M. Benedetto

ABSTRACTLead zirconate-titanate (PZT) thin films were prepared by the laser ablation technique. The PZT (Zr/Ti=53/47) target was irradiated using a focused q-switched Nd:YAG laser (15 ns, 100 mJ at 1.064 μ;m). The as-deposited films were amorphous as indicated by X-ray powder patterns, but crystallized readily with brief annealing above 650°C. The dielectric constant and the resistivity of the crystallized films were studied using a parallel-plate type capacitor structure.


2007 ◽  
Vol 336-338 ◽  
pp. 173-176
Author(s):  
Hui Qing Fan ◽  
Lai Jun Liu ◽  
Xiu Li Chen ◽  
Jie Zhang ◽  
Wei Wang

Barium modified lead zirconate titanate (PBZT) thin films were grown epitaxially on Pt/Ti/SiO2/Si substrates by radio-frequency magnetron sputtering deposition and characterized by X-ray diffraction and scanning electron microscopy. Depending on the growth condition, a wide variation of crystal structure and morphology was evolved in PBZT thin films. The formation of phase structure and pyrochlore phase was strongly dependent on the oxygen partial pressure and re-evaporation of lead from the films during the deposition. Perovskite films were obtained by optimizing the deposition conditions and analyzed by the ferroelectric hysteresis (P~E).


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