摘要:

There has been increasing interest in ferroelectric lead zirconate titanate (PZT) films for the applications in piezoelectric and pyroelectric devices. Many potential applications require a film thickness of above 10 μm for higher force, better sensitivity and stability. But it is very difficult to fabricate the PZT thick film on the silicon substrate because of the volatility of PbO and the interdiffusion of the Pb and Si through the bottom electrode during the sintering at normal temperatures (such as above 1200°C). We speculated densification and reaction mechanism of the PZT thick films fabricated at relatively low temperature (under 1000°C) without sintering aids. The PZT thick films were screen-printed on Pt / Al2O3substrate using a paste of PbO, ZrO2and TiO2powder mixture. Highly densified PZT thick films could be fabricated on Pt / Al2O3substrate at 1000°C, and we achieved the density, remanent polarization, coercive field, dielectric permittivity, dissipation factor and breakdown field of 98%, 10 μC/cm2and 20 kV/cm, 540, 0.009 and 15 MV/m, respectively. The results show the possibility of densification of the PZT thick film at relatively low temperature without sintering aids, and the results are promising for the use of PZT thick films in various applications.

ISSN:1058-4587    

DOI:10.1080/10584580008222257

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

650°C process of SrBi2Ta2O9(SBT) has been achieved through the use of new metal organic deposition (MOD) solution and the optimization of the deposition conditions. The sample showed a high remnant polarization (2Pr) of 14 μC/cm2@3V, a low leakage current of 10–8A/cm2or less @3V, and a fatigue-free nature. We believe this processing will realize high-density FeRAM integration of SBT.

ISSN:1058-4587    

DOI:10.1080/10584580008222258

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

PbZr0.65Ti0.35O3and Pb0.91La0.09Zr0.65Ti0.35O3thin films with thickness of around 100 nm were prepared by the chemical solution deposition technique on Si (100) substrate. Complex metal alkoxide precursors were synthesized by alcoholisis and alcohol exchange reactions starting from metallorganics compounds. NMR spectroscopic techniques,1H and13C, and FTIR analysis were used to study the arrangement of the metals and oxygen in the precursor molecules. The films were deposited on Si (100) by spin coating technique and thermal treated by Rapid Thermal Processing for film crystallization. The thermal evolution and structural characterization were performed by DTA-TG/FTIR and by glazing incidence XRD and XRD powder. A PLZT powder with a well-crystallized perovskite structure was obtained at 700°C free of pyrochlore phase whereas the PLZT film exhibits a distorted perovskite structure and residual pyrochlore. The PZT films were less crystallized. The silicon substrate affects the crystal structure of the film. The residual acetylacetonate groups in the precursor of PLZT, would reduce the clustering of Zirconium species.

ISSN:1058-4587    

DOI:10.1080/10584580008222259

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Effects of insulator layers of Metal(Au)/Ferroelectrics(PZT)/Insulator/Si (MFIS) structure capacitors are investigated for non-destructive type non-volatile memory device applications. Various high dielectric oxide layers such as Al2O3, Ta2O5, TiO2and ZrO2were fabricated by reactive sputtering as insulating layers. The oxide insulators give significant impacts on the morphologies of PZT layer and the properties of capacitors. It is noted that the oxide layers with small thermal expansions (<6x10–6/°C) coefficient caused cracks on PZT films during PZT crystallization annealing. The effects of insulators as a diffusion barrier are also comparatively studied using Auger electron spectroscopy. In addition, the characteristics of high dielectric solid solution, such as titanium oxide-zirconium oxide, are also studied.

ISSN:1058-4587    

DOI:10.1080/10584580008222260

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Laser annealing studies on CSD derived (Ba, Sr)TiO3thin films were performed using a KrF-Excimer laser emitting light at a wavelength of λ=248nm with pulse duration of λ=20ns. The pulse energies and the number of pulses within one crystallization process were varied over a range of 10mJ/cm2to 200mJ/cm2and 10 to 10000 pulses. The appearance of crystallization was identified using microstructural analytical methods. The crystallization depth obtained was in the range of 30–150nm. Several different kinds of damage were identified depending on the laser and deposition parameters. The experimental results are interpreted by modeling of the heat distribution in the material using finite element method.

ISSN:1058-4587    

DOI:10.1080/10584580008222261

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

BaTiO3and SrTiO3thin films were prepared by reduced-pressure metalorganic chemical vapor deposition. Ba(thd)2-di-tri, or Sr(thd)2, and Ti(OPr1)2-(thd)2were dissolved in diglyme and were delivered by an aerosol-assisted non-contact vaporizer. Growth kinetics of the thin films was studied as a function of growth temperature, liquid source concentration and molar ratio of the metalorganic precursors. The mechanisms of composition control, crystallization and phase formation of the thin films were investigated over a wide range of stoichiometry.

ISSN:1058-4587    

DOI:10.1080/10584580008222262

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

PLZT 5/30/70 sols for thin film deposition have been prepared from lead oxide, lanthanum nitrate and transition metal n-butoxides in a series of etheralcohols. After the low temperature heat treatment at 200°C for 2 minutes and at 400°C for 5 minutes the PLZT 5/30/70 thin films crystallize in the perovskite phase and exhibit ferroelectric response. To our knowledge, this is the lowest crystallization temperature of perovskite phase observed for titanium rich PLZT.

ISSN:1058-4587    

DOI:10.1080/10584580008222263

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Perovskite SrRuO3(SRO) layer was, for the first time, been successfully synthesized by using metal-organic decomposition (MOD) process. The presence of SRO buffer layer on Pt(Si) substrates has significantly enhanced the crystallization and densification behavior of the subsequently deposited Pb(Zr0.52Ti0.48)O3films. The pyrochlore free perovskite phase can be obtained by post-annealing the PZT/SRO/Pt(Si) films at 500°C, which is 50°C lower than that needed in PZT/Pt(Si) films. The fine grain (∼0.3 μm) microstructure can be attained by post-annealing at 650°C for PZT/SRO/Pt(Si) films and 700°C for PZT/Pt(Si) films. The ferroelectric hysteresis properties of the two PZT films are comparable to each other. The leakage current properties of PZT/SRO/Pt(Si) films increased pronouncedly with post-annealing temperature, resulting in inferriar leakage behavior to PZT/Pt(Si) films.

ISSN:1058-4587    

DOI:10.1080/10584580008222264

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Thin films of PbTiO3, BaTiO3and (PbxBa1-x)TiO3(PBT) have been prepared by metal-organic chemical vapor deposition using a horizontal reactor with an aerosol-assisted liquid delivery system. Structural and electrical properties have been investigated as a function of the lead content x. First results on PBT thin films grown on platinized silicon substrates show, for x < 0.8, an increasing tetragonal distortion of the lattice cell (c/a >1), and accompanying ferroelectric behavior which is similar to the bulk material. For smaller lead content (x < 0.8) no ferroelectric behavior is established and a small tetragonal distortion of opposite type (c/a <1) is observed. This distortion is attributed to a thermally induced tensile film stress and may be responsible for the suppression of the ferroelectric phase transition.

ISSN:1058-4587    

DOI:10.1080/10584580008222265

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor

摘要:

Pb1.1(Zr0.7Ti0.3)O3(PZT) thin films with different preferred orientation were fabricated from different precursor solutions by the sol-gel method on (111)-Pt/Ti/SiO2/Si-(100) substrates. The concentration of acetic acid was found to affect strongly the attribution and distribution of stresses in the films, and then to further affect the crystal orientation of the films. The reproducible microstructure and textures can be obtained by modifying the [Acet]/[Ti] molar ratio. To confirm this stress effect, an external stress was applied to induce the oriented growth of the thin films. The mechanism of the nucleation, growth and orientation of the films is discussed.

ISSN:1058-4587    

DOI:10.1080/10584580008222266

出版商:Taylor & Francis Group    

年代:2000

数据来源: Taylor