Micromechanical modeling of ferroelectric films

2006 ◽  
Vol 21 (3) ◽  
pp. 557-562 ◽  
Author(s):  
J.E. Huber
Keyword(s):  
Thin Film ◽  
Stress State ◽  
Residual Stresses ◽  
Micromechanical Modeling ◽  
Film Material ◽  
Ferroelectric Films ◽  
Self Consistent ◽  
Non Volatile Memory ◽  
Preliminary Study ◽  
Constrained Behavior

Ferroelectric films are growing in significance as non-volatile memory devices, sensors, and microactuators. The stress state of the film, induced by processing or constraints such as the substrate, strongly affects device behavior. Thus, it is important to be able to model the coupled and constrained behavior of film material. This work presents a preliminary study of the application of micromechanical modeling to ferroelectric films. A self-consistent micromechanics model developed for bulk ferroelectrics is adapted for thin film behavior by incorporating several features of the microstructure, mechanical clamping by the substrate, residual stresses, and the crystallographic orientation of the film.

Micromechanical Modelling of Ferroelectric Films

2005 ◽  
Vol 881 ◽  
Author(s):  
J. E. Huber
Keyword(s):  
Thin Film ◽  
Stress State ◽  
Residual Stresses ◽  
Grain Structure ◽  
Film Material ◽  
Ferroelectric Films ◽  
Micromechanical Modelling ◽  
Self Consistent ◽  
Non Volatile Memory ◽  
Preliminary Study

AbstractFerroelectric films are growing in significance as non-volatile memory devices, sensors and microactuators. The stress state of the film, induced by processing or constraints such as the substrate, strongly affects device behaviour. Thus it is important to be able to model the coupled and constrained behaviour of film material. This work presents a preliminary study of the application of micromechanical modelling to ferroelectric films. A self-consistent micromechanics model developed for bulk ferroelectrics is adapted for thin film behaviour by incorporating features such as grain structure, mechanical clamping by the substrate, residual stresses, and crystallographic orientation of the film.

scholarly journals Modeling Methodology for Stress Determination by XRD in Polycrystalline Materials

2014 ◽  
Vol 996 ◽  
pp. 106-111 ◽  
Author(s):  
Stéphane Dufrenoy ◽  
Thierry Chauveau ◽  
Renald Brenner ◽  
Christophe Fontugne ◽  
Brigitte Bacroix
Keyword(s):  
Residual Stresses ◽  
Quantitative Estimate ◽  
Tensile Loading ◽  
Micromechanical Modeling ◽  
Polycrystalline Materials ◽  
Stress Determination ◽  
Modeling Methodology ◽  
Self Consistent ◽  
Polycrystalline Model

To get a quantitative estimate of residual stresses in polycrystals from XRD measurements, a micromechanical modeling is required, except in particular cases. The most widely used method is only valid for homogeneous and isotropic samples. We present here the possibility to determine residual stresses by coupling measurements with the portable INELTMXsolo equipement with a self-consistent polycrystalline model. This methodology may take into account texture and intergranular stresses induced by thermomechanical treatments. One example obtained for titanium subjected to tensile loading illustrates the methodology.

Abnormal infrared effects of nanometer scale thin film material of PtPd alloy in CO adsorption

2001 ◽  
Vol 46 (17) ◽  
pp. 1439-1442 ◽  
Author(s):  
Zhi Chen ◽  
Shigang Sun ◽  
Nan Ding ◽  
Zhiyou Zhou
Keyword(s):  
Thin Film ◽  
Co Adsorption ◽  
Nanometer Scale ◽  
Film Material ◽  
Thin Film Material

Preparation and Characterization of SnO2/WO3/MWCNT Nanocomposite Thin Film for NO2 Gas Sensor

2010 ◽  
Vol 129-131 ◽  
pp. 99-103
Author(s):  
Wei Lin ◽  
Shi Zhen Huang ◽  
Wen Zhe Chen
Keyword(s):  
Thin Film ◽  
Gas Sensor ◽  
Photoelectron Spectroscopy ◽  
Mixed Oxides ◽  
Surface Composition ◽  
Chemical Elements ◽  
Film Material ◽  
Nanocomposite Thin Film ◽  
Oxide Compound ◽  
Thin Film Material

A novel nanocomposite thin film material of SnO2/WO3 metal oxide compound doped by multi-walled carbon nanotubes (MWCNT) and its corresponding gas sensor were prepared by radio frequency (RF) reactive magnetron sputtering. The surface composition and chemical elements of the thin film material were respectively analyzed and validated by X-ray diffraction (XRD) and photoelectron spectroscopy (XPS). The influencing factors of gas sensing properties were studied and the test results of gas sensor were analyzed. The results indicated that the detection using the composite material gas sensors for low concentration NO2 toxic gas could be greatly improved by MWCNTs which were doped on the mixed oxides matrix. A possible mechanism explaining the behaviour of the thin film gas sensor was introduced.

The Optical Properties of Thin Films Tin Oxide with Triple Doping (Aluminum, Indium, and Fluorine) for Electronic Device

2021 ◽  
Vol 317 ◽  
pp. 477-482
Author(s):  
Aris Doyan ◽  
Susilawati ◽  
Muhammad Taufik ◽  
Syamsul Hakim ◽  
Lalu Muliyadi
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Activation Energy ◽  
Optical Properties ◽  
Tin Oxide ◽  
Electronic Device ◽  
Film Material ◽  
Mass Percentage ◽  
Gap Energy ◽  
As Doping

Tin oxide (SnO2) thin film is a form of modification of semiconductor material in nanosize. The thin film study aims to analyze the effect of triple doping (Aluminum, Indium, and Fluorine) on the optical properties of SnO2: (Al + In + F) thin films. Aluminum, Indium, and Fluorine as doping SnO2 with a mass percentage of 0, 5, 10, 15, 20, and 25% of the total thin-film material. The addition of Al, In, and F doping causes the thin film to change optical properties, namely the transmittance and absorbance values ​​changing. The transmittance value is 67.50, 73.00, 82.30, 87.30, 94.6, and 99.80 which is at a wavelength of 350 nm for the lowest to the highest doping percentage, respectively. The absorbance value increased with increasing doping percentage at 300 nm wavelength of 0.52, 0.76, 0.97, 1.05, 1.23, and 1.29 for 0, 5, 10, 15, 20, and 25% doping percentages, respectively. The absorbance value is then used to find the gap energy of the SnO2: (Al + In + F) thin film of the lowest doping percentage to the highest level i.e. 3.60, 3.55, 3.51, 3.47, 3.42, and 3.41 eV. Thin-film activation energy also decreased with values of 2.27, 2.04, 1.85, 1.78, 1.72, and 1.51 eV, respectively for an increasing percentage of doping. The thin-film SnO2: (Al + In + F) which experiences a gap energy reduction and activation energy makes the thin film more conductive because electron mobility from the valence band to the conduction band requires less energy and faster electron movement as a result of the addition of doping.

About Residual Stress State of Castings: The Case of HPDC Parts and Possible Advantages through Semi-Solid Processes

2022 ◽  
Vol 327 ◽  
pp. 272-278
Author(s):  
Elisa Fracchia ◽  
Federico Simone Gobber ◽  
Claudio Mus ◽  
Yuji Kobayashi ◽  
Mario Rosso
Keyword(s):  
Residual Stress ◽  
Stress State ◽  
Residual Stresses ◽  
Casting Process ◽  
Ray Method ◽  
Premature Failure ◽  
Thin Walls ◽  
Residual Stress State ◽  
Semi Solid ◽  
Pressure Die Casting

Nowadays, one of the most crucial focus in the aluminium-foundry sector is the production of high-quality castings. Mainly, High-Pressure Die Casting (HPDC) is broadly adopted, since by this process is possible to realize aluminium castings with thin walls and high specific mechanical properties. On the other hand, this casting process may cause tensile states into the castings, namely residual stresses. Residual stresses may strongly affect the life of the product causing premature failure of the casting. Various methods can assess these tensile states, but the non-destructive X-Ray method is the most commonly adopted. Namely, in this work, the residual stress analysis has been performed through Sinto-Pulstec μ-X360s. Detailed measurements have been done on powertrain components realized in aluminium alloy EN AC 46000 through HPDC processes to understand and prevent dangerous residual stress state into the aluminium castings. Furthermore, a comparison with stresses induced by Rheocasting processes is underway. In fact, it is well known that Semi-Solid metal forming combines the advantages of casting and forging, solving safety and environmental problems and possibly even the residual stress state can be positively affected.

Sign in / Sign up

Export Citation Format

Share Document