Internal Stress In Sputtered Silver Nickel Thin Films And Multilayers: Sputtering Pressure And Thickness Effects

1999 ◽  
Vol 562 ◽  
Author(s):  
P. Gergaud ◽  
H. Yang ◽  
C. PéLissonnier-Grosjean ◽  
A. J. Bottger ◽  
P. Sandström ◽  
...  
Keyword(s):  
Thin Films ◽  
Internal Stress ◽  
Layer Thickness ◽  
Lattice Parameter ◽  
Free Lattice ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Nickel Thin Films ◽  
The Individual ◽  
20 Nm

ABSTRACTNanometer thick films are often in a state of high residual stress. This may strongly influence physical properties such as magnetic anisotropy. The aim of our study is to investigate whether the overall stress in multilayers may be tailored via the control of the sputtering parameters or of the individual thicknesses. The coatings investigated were deposited at room temperature by magnetron sputtering on oxidised silicon substrates. Ag/Ni multilayers of superperiod between 4 to 20 nm and thin films (Ag or Ni) 200 nm thick have been deposited under a krypton partial pressure varying between 1 and 8 mTorr. Internal stress measurements were performed by curvature method and x-ray diffraction sin2ψ method. The latter one allows the determination of the stress and of the stress-free lattice parameter in the Ag or the Ni layers whereas the first one gives rise to a measure of the average stress in the coating. The main results are the followings: (i) The stress in Ni thin films changes from compressive to tensile at a pressure between 2 and 5 mTorr whereas Ag thin films are sligthly tensile whatever the pressure; (ii) The stress in multilayers is tensile in Ag and Ni and decreases with sublayer thickness; (iii) The stress free lattice parameter of Ag in thin films or multilayers is independent of the Kr pressure and of the layer thickness and is equal to the bulk value; (iv) On the opposite, the stress-free lattice parameter of nickel decreases with the layer thickness in multilayers and is equal to the bulk value in thin films. These results are discussed in terms of the respective influence of interfacial intermixing and atomic peening mechanism.

Effects of Individual Layer Thickness on the Structure and Electrical Properties of Sol-Gel-Derived Ba0.8Sr0.2TiO3 Thin Films

2012 ◽  
Vol 621 ◽  
pp. 23-26
Author(s):  
Wei Rao ◽  
Ding Guo Li ◽  
Hong Chun Yan
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Layer Thickness ◽  
Sol Gel ◽  
Layer By Layer ◽  
Individual Layer ◽  
Individual Layer Thickness ◽  
Columnar Grains ◽  
The Individual ◽  
20 Nm

Ba0.8Sr0.2TiO3 thin films were prepared with various individual layer thicknesses using a sol– gel process. The individual layer thickness strongly affected the structure, ferroelectricity, and dielectric properties of the films. The films prepared with an individual layer thickness of 60 nm showed small equiaxed grains, cubic structure, temperature-independent dielectric constant, and no ferroelectricity. The films prepared with an individual layer thickness of 8 nm showed columnar grains, tetragonal structure, good ferroelectricity, and two dielectric peaks in the dielectric constant–temperature curve. The individual layer thickness for layer-by-layer homoepitaxy growth that resulted in columnar grains was <20 nm.

Residual Stress and Microstructure of CU/W Multilayers

1993 ◽  
Vol 308 ◽  
Author(s):  
Ph. Goudeau ◽  
K.F. Badawi ◽  
A. Naudon ◽  
N. Durand
Keyword(s):  
Solid Solution ◽  
Residual Stress ◽  
Ion Irradiation ◽  
Lattice Parameter ◽  
Free Lattice ◽  
Curvature Radius ◽  
X Ray Diffraction ◽  
X Ray ◽  
Microstructure Modification ◽  
20 Nm

ABSTRACTWe have determined residual stresses and the layer microstructure in as-prepared Cu/W multilayers of different periods ranging from 5.2 to 20 nm by both X-ray diffraction and the curvature radius method. The magnitude of the principal in-plane stress is large in the W layers (around - 6 GPa) and small in the Cu layers (-0.5 - + 0.5 GPa). The stress state is independent of the multilayer period. Under the compressive stress, the W cubic unit cell becomes monoclinic-like. The stress-free lattice parameter is found higher than the bulk one.We also studied the stress relaxation and the layer microstructure modification in W layers induced by Kr ion irradiation., the relaxation is almost achieved after only low fluence irradiations and the decrease of the stress-free lattice parameter in W layers observed for higher fluences is attributed to the formation of a sursaturated solid solution W(Cu).

scholarly journals Thickness-dependent piezoelectric behaviour and dielectric properties of lanthanum modified BiFeo3 thin films

2011 ◽  
Vol 5 (1) ◽  
pp. 31-39 ◽  
Author(s):  
Glenda Biasotto ◽  
Francisco Moura ◽  
Cesar Foschini ◽  
Elson Longo ◽  
Jose Varela ◽  
...  
Keyword(s):  
Thin Films ◽  
Lattice Parameter ◽  
Hexagonal Structure ◽  
Piezoelectric Response ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Bifeo3 Thin Films ◽  
Entire Thickness

Bi0.85La0.15FeO3 (BLFO) thin films were deposited on Pt(111)/Ti/SiO2 /Si substrates by the soft chemical method. Films with thicknesses ranging from 140 to 280 nm were grown on platinum coated silicon substrates at 500?C for 2 hours. The X-ray diffraction analysis of BLFO films evidenced a hexagonal structure over the entire thickness range investigated. The grain size of the film changes as the number of the layers increases, indicating thickness dependence. It is found that the piezoelectric response is strongly influenced by the film thickness. It is shown that the properties of BiFeO3 thin films, such as lattice parameter, dielectric permittivity, piezoeletric coefficient etc., are functions of mis?t strains.

scholarly journals Elaboration of nitride thin films by reactive sputtering

2006 ◽  
Vol 59 (2) ◽  
pp. 225-232 ◽  
Author(s):  
Pierre Yves Jouan ◽  
Arnaud Tricoteaux ◽  
Nicolas Horny
Keyword(s):  
Thin Films ◽  
Compressive Stress ◽  
Bias Voltage ◽  
Substrate Surface ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
A Value ◽  
Dc Reactive Magnetron Sputtering ◽  
Nitrogen Contents

The aim of this paper is first a better understanding of DC reactive magnetron sputtering and its implications, such as the hysteresis effect and the process instability. In a second part, this article is devoted to an example of specific application: Aluminium Nitride. AlN thin films have been deposited by reactive triode sputtering. We have studied the effect of the nitrogen contents in the discharge and the RF bias voltage on the growth of AlN films on Si(100) deposited by triode sputtering. Stoichiometry and crystal orientation of AlN films have been characterized by means of Fourier-transform infrared spectroscopy, X-ray diffraction and secondary electron microscopy. Dense and transparent AlN layers were obtained at high deposition rates. These films have a (002) orientation whatever the nitrogen content in the discharge, but the best crystallised ones are obtained at low value (10%). A linear relationship was observed between the AlN lattice parameter "c" (perpendicular to the substrate surface) and the in-plane compressive stress. Applying an RF bias to the substrate leads to a (100) texture, and films become amorphous. Moreover, the film's compressive stress increases up to a value of 8GPa before decreasing slowly as the bias voltage increases.

Characterization of bulk crystals of transition metal doped ZnO for spintronic applications

2003 ◽  
Vol 799 ◽  
Author(s):  
M. H. Kane ◽  
R. Varatharajan ◽  
Z. C. Feng ◽  
S. Kandoor ◽  
J. Nause ◽  
...  
Keyword(s):  
Transition Metal ◽  
Lattice Parameter ◽  
X Ray Diffraction ◽  
Absorption Bands ◽  
Growth Technique ◽  
Undoped Material ◽  
Doped Zno ◽  
Metal Doped ◽  
The Individual

ABSTRACTIn this work, we report on the material properties of ZnO doped with Mn, Co, and Fe grown by a modified melt growth technique. X-ray diffraction measurements show that transition metals can be incorporated on Zn sites; an increase in the lattice parameter is apparent with increasing doping level. UV-visible transmission and reflectance measurements have also been performed. Absorption bands in the visible regime are distinctive to the individual transition metal dopants. A noticeable shift in the optical band edge has been observed from these Mn/Co/Fe-doped ZnO crystals in comparison with the undoped material. ZnO may also provide a suitable platform for the incorporation of transition metal elements through high temperature near equilibrium growth processes; however, further work is required in order to employ these materials for spintronic applications.

The Sensitivity of V2O5:Sm2O3 Thin Films against NO2 Toxic Gas

2021 ◽  
Vol 19 (3) ◽  
pp. 69-77
Author(s):  
A.J. Noori ◽  
R.A. Ahmed ◽  
I.M. Ibrahim
Keyword(s):  
Thin Films ◽  
Energy Gap ◽  
Homogeneous Distribution ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Laser Method ◽  
Operation Temperature ◽  
Best Response ◽  
Diffraction Peaks ◽  
P Type

Vanadium oxide V2O5 thin films with variation doping ratios of Sm2O5 (2, 4, 6, and 8 % wt.) on corn glass and p- type silicon substrates were prepared by pulsed laser method. The X-ray diffraction peaks for V2O5 decreases with doping ratio of Sm2O3. FESEM images for V2O5 and doped thin films illustrates clusters with a homogeneous distribution in nano scale. The energy gap varied upon the increment of doping concentration, starting from 2.610 eV to 2.7 eV. Gas sensor measurement of pure and doped V2O5 demonstrated a sensitivity to NO2 gas, and the sensitivity expanded upon the increment of operation temperature. The greatest sensitivity was found to be about 99%, while best response time of 10s and recovery time of 18s were recorded using the 4% Sm2O3 sample at 50 °C.

Epitaxial Ferroelectric BaTiO3 Thin Films for Microphotonic Applications

2000 ◽  
Vol 637 ◽  
Author(s):  
F. Niu ◽  
A.R. Teren ◽  
B.H. Hoerman ◽  
B.W. Wessels
Keyword(s):  
Thin Films ◽  
Chemical Vapor ◽  
Silicon Substrates ◽  
X Ray Diffraction ◽  
Insulating Layer ◽  
Ferroelectric State ◽  
Transmission Electron ◽  
Electro Optic ◽  
Metal Organic ◽  
Mgo Layers

AbstractEpitaxial ferroelectric BaTiO3 thin films have been developed as a material for microphotonics. Efforts have been directed toward developing these materials for thin film electro-optic modulators. Films were deposited by metalorganic chemical vapor deposition (MOCVD) on both MgO and silicon substrates. The electro-optic properties of the thin films were measured. For BaTiO3 thin films grown on (100) MgO substrates, the effective electro-optic coefficient, reff depended on the magnitude and direction of the electric field. Coefficients as high as 260 pm/V have been measured. Investigation of BaTiO3 films on silicon has been undertaken. Epitaxial BaTiO3 thin films were deposited by MOCVD on (100) MgO layers grown on silicon (100) substrates by metal-organic molecular beam epitaxy (MOMBE). The MgO serves as the low index optical cladding layer as well as an insulating layer. X-ray diffraction and transmission electron microscopy (TEM) indicated that BaTiO3 was epitaxial with an orientational relation given by BaTiO3 (100)//Si (100) and BaTiO3[011]//Si [011]. Polarization measurements indicated that the BaTiO3 epitaxial films on Si were in the ferroelectric state.

Formation and characterization of high-density silver nanoparticles embedded in silica thin films by “in situ” self-reduction

2001 ◽  
Vol 16 (10) ◽  
pp. 2934-2938 ◽  
Author(s):  
G. Compagnini ◽  
M. M. Fragal´ ◽  
L. D'Urso ◽  
C. Spinella ◽  
O. Puglisi
Keyword(s):  
Thin Films ◽  
Silver Nanoparticles ◽  
High Density ◽  
Silver Particles ◽  
X Ray Diffraction ◽  
Optical Extinction ◽  
Organometallic Precursor ◽  
Silica Thin Films ◽  
20 Nm

Silver nanoparticles (10–20 nm) embedded into silica thin films have been obtained through the use of a silver organometallic precursor compound dissolved in Spin-On-Glass and subsequently spinned onto suitable substrates. In this paper we present a study of the shape, size, and distribution of silver particles through the use of microscopes, x-ray diffraction, and optical extinction. It has been observed that the obtained films are stable for annealing up to 500 °C with a progressive degradation above this temperature. Furthermore it is possible to obtain high-density silver particles up to 15% in weight without affecting the cluster size and shape.

Effects of ZnO layer on anisotropy magnetoresistance of Ni81Fe19 films

2014 ◽  
Vol 28 (06) ◽  
pp. 1450043 ◽  
Author(s):  
Shuyun Wang ◽  
Yuanmei Gao ◽  
Tiejun Gao ◽  
Yuan He ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetic Properties ◽  
Magnetron Sputtering ◽  
Substrate Temperature ◽  
Layer Thickness ◽  
Magnetic Thin Films ◽  
Anisotropic Magnetoresistance ◽  
Experimental Conditions ◽  
Method Effects ◽  
20 Nm

A series of Ta (4 nm)/ ZnO (t nm )/ Ni 81 Fe 19 (20 nm)/ ZnO (t nm )/ Ta (3 nm) magnetic thin films were prepared on lower experimental conditions by magnetron sputtering method. Effects of ZnO layer thickness and substrate temperature on anisotropic magnetoresistance and magnetic properties of these Ni 81 Fe 19 films have been investigated. The experiment results show that the anisotropic magnetoresistance value of the Ni 81 Fe 19 film is enhanced with the increasing of the inserted ZnO layer thickness. When the ZnO thickness is 2 nm, the anisotropic magnetoresistance value achieves the maximum. In addition, the anisotropic magnetoresistance of the Ni 81 Fe 19 film is also enhanced with the increasing of substrate temperature, and when the temperature is 450°C, the anisotropic magnetoresistance reaches the maximum. The anisotropic magnetoresistance value of 20 nm Ni 81 Fe 19 films with 2 nm ZnO layer can achieve 3.63% at 450°C which is enhanced 11.6% compare with the films without ZnO layer.

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