Mechanical spectroscopy of nanocrystalline aluminum films: effects of frequency and grain size on internal friction

Al thin film is extensively used in micro-electromechanical systems (MEMS) and electronic interconnections; however, most previous research has concentrated on their quasi-static properties and applied their designs on larger scales. The present study designed a paddle-like cantilever specimen with metal films deposited on the upper surface to investigate the quasi-static properties of Al thin film at room temperature under high vacuum conditions at microscopic scales. Energy loss was determined using a decay technique in the oscillation amplitude of a vibrating structure following resonant excitation. Grain size and film thickness size were strictly controlled considering the quasi-static properties of the films. This study found that the internal friction of ultra-thin and thin Al films was more dependent on the grain boundaries than film thickness.

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High Temperature Internal Friction in Fine Grain and Nano-Crystalline Zirconia

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.184.271 ◽

2012 ◽

Vol 184 ◽

pp. 271-276 ◽

Cited By ~ 1

Author(s):

P. Simas ◽

M. Castillo-Rodríguez ◽

M.L. Nó ◽

S. De-Bernardi ◽

D. Gómez ◽

...

Keyword(s):

Grain Size ◽

High Temperature ◽

Internal Friction ◽

New Technologies ◽

Mechanical Spectroscopy ◽

Spectra Analysis ◽

High Temperature Mechanical Properties ◽

Fine Grain ◽

Nano Crystalline ◽

The One

Engineering ceramics are being developed to improve their high-temperature mechanical properties and in particular creep resistance. Recently the production of fine grain ceramics undergoes another step-forward with the development of new technologies to produce nanocrystalline materials. The question is whether the properties depending on the grain size can be extrapolated at nanoscale or, on the contrary, new microscopic mechanisms could appear to be dominant at this nanometer grain size. In the present work we study, by mechanical spectroscopy, the high temperature behavior up to 1350°C of a fine grain Zirconia and a nanocrystalline Zirconia sintered in a conventional way. A new forced torsion pendulum, recently built, has been used for the mechanical spectroscopy measurements. The high temperature background (HTB) of internal friction has been measured as a function of temperature for different frequencies in both materials. The analysis of the HTB shows that the fine grain Zirconia exhibits a single process of defects mobility, with an apparent activation enthalpy similar to the one measured by creep. On the contrary, the HTB of the nanocrystalline sample becomes more complex, showing a much higher energy loss, which will be discussed at the light of the internal friction spectra analysis.

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Texture and Microstructure Effects on Electromigration Behavior of Aluminum Metallization

MRS Proceedings ◽

10.1557/proc-225-21 ◽

1991 ◽

Vol 225 ◽

Cited By ~ 10

Author(s):

D. B. Knorr ◽

K. P. Rodbell ◽

D. P. Tracy

Keyword(s):

Grain Size ◽

Standard Deviation ◽

Pure Aluminum ◽

Time To Failure ◽

X Ray Diffraction ◽

Aluminum Films ◽

Failure Data ◽

Transmission Electron ◽

Aluminum Metallization ◽

Microstructure Effects

ABSTRACTPure aluminum films are deposited under a variety of conditions to vary the crystallographic texture. After patterning and annealing at 400°C for 1 hour, electromigration tests are performed at several temperatures. Failure data are compared on the basis of t50 and standard deviation. Microstructure is quantified by transmission electron microscopy for grain size and grain size distribution and by X-ray diffraction for texture. A strong (111) texture significantly improves the electromigration lifetime and decreases the standard deviation in time to failure. This improvement correlates with both the fraction and sharpness of the (111) texture component.

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Mechanical Spectroscopy Study on the Light Soaking Effect on Hydrogenated Amorphous Silicon

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.184.416 ◽

2012 ◽

Vol 184 ◽

pp. 416-421 ◽

Cited By ~ 1

Author(s):

H. Mizubayashi ◽

I. Sakata ◽

H. Tanimoto

Keyword(s):

Internal Friction ◽

Temperature Dependence ◽

Amorphous Silicon ◽

Hydrogenated Amorphous Silicon ◽

Wide Distribution ◽

Activation Energies ◽

Mechanical Spectroscopy ◽

Induced Changes ◽

Mild Temperature ◽

Hydrogenated Amorphous

For hydrogenated amorphous silicon (a-Si:H) films deposited at temperatures between 423 K and 623 K (a-Si:H423Kand so on), the light-induced changes in the internal friction between 80 K and 400 K were studied. The internal friction is associated with H2motion in microvoid networks, and shows the mild temperature dependence between about 80 K and 300 K (Q-180-300K) and the almost linear increase above 300 K (Q-1>300K). BothQ-180-300KandQ-1>300Kdecrease with increasing the deposition temperature, and show the mild temperature dependence ina-Si:H623K. The white light soaking with 100 mW/cm2(WLS100and so on) below 300 K caused a change inQ-180-300Kand no changes inQ-1>300K, respectively, and the light-induced changes inQ-180-300Krecovered after annealing at 423 K. The wide distribution of activation energies for H2motions between microvoids indicate that most of neighboring microvoids are connected through windows, i.e., the microvoid networks are existing ina-Si:H, and the spatially loose or solid structures are responsible for the low or high activation energies for the H2motion between microvoids, respectively. Furthermore, the light-induced hydrogen evolution (LIHE) was observed for WLS200to WLS400in a vacuum between 400 and 500 K, resulting in the disappearance of the internal friction due to the H2motion in the microvoid network.

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Internal friction of nanocrystalline aluminum prepared by plasma evaporation and compaction

Scripta Materialia ◽

10.1016/s1359-6462(00)00705-3 ◽

2001 ◽

Vol 44 (7) ◽

pp. 1043-1048 ◽

Cited By ~ 16

Author(s):

B Cai ◽

Q.P Kong ◽

P Cui ◽

H.T Cong ◽

X.K Sun

Keyword(s):

Internal Friction ◽

Nanocrystalline Aluminum

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High-Temperature Mechanical Relaxation due to Dislocation Motion inside Dislocation Networks

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.137.21 ◽

2008 ◽

Vol 137 ◽

pp. 21-28 ◽

Cited By ~ 7

Author(s):

Andre Rivière ◽

Michel Gerland ◽

Veronique Pelosin

Keyword(s):

Internal Friction ◽

Relaxation Effect ◽

Dislocation Motion ◽

Relaxation Peak ◽

Mechanical Relaxation ◽

In Situ Tem ◽

Mechanical Spectroscopy ◽

Internal Friction Peak ◽

First Case ◽

Dislocation Walls

Internal friction peaks observed in single or polycrystals are clearly due to a dislocation relaxation mechanism. Because a sample observed by transmission electron microscopy (TEM) often exhibits in the same time various dislocation microstructures (isolated dislocations, dislocation walls, etc.) it is very difficult to connect the observed relaxation peak with a particular dislocation microstructure. Using isothermal mechanical spectroscopy (IMS), it is easier to compare, for instance, the evolution of a relaxation peak with measurement temperature to the microstructural evolution observed by in-situ TEM at the same temperatures. IMS was used to study a relaxation peak in a 5N aluminium single crystal firstly 1% cold worked and then annealed at various temperatures. TEM experiments performed in the same material at various temperatures equal to the temperatures used for the damping experiments made possible to link this internal friction peak with a relaxation effect occurring inside dislocation walls. In two other experiments in a 4N aluminium polycrystal and in a metal matrix composite with SiC whiskers, it is shown that the observed relaxation peaks are connected to the motion of dislocations inside polygonization boundaries in the first case and in dislocation pile-ups around each whisker in the second one. Theoretical models proposed to explain such relaxation peaks due to a dislocation motion inside a dislocation wall or network are discussed.

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Critical Assessment Of The Issues In The Application Of Hilbert Transform To Compute The Logarithmic Decrement

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0267 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1105-1108

Author(s):

M. Majewski ◽

L.B. Magalas

Keyword(s):

Internal Friction ◽

Hilbert Transform ◽

Computing Methods ◽

Critical Assessment ◽

Logarithmic Decrement ◽

High Dispersion ◽

Mechanical Spectroscopy ◽

Transform Method ◽

Twin Method ◽

Selection Of

Abstract The parametric OMI (Optimization in Multiple Intervals), the Yoshida-Magalas (YM) and a novel Hilbert-twin (H-twin) methods are advocated for computing the logarithmic decrement in the field of internal friction and mechanical spectroscopy of solids. It is shown that dispersion in experimental points results mainly from the selection of the computing methods, the number of oscillations, and noise. It is demonstrated that conventional Hilbert transform method suffers from high dispersion in internal friction values. It is unequivocally demonstrated that the Hilbert-twin method, which yields a ‘true envelope’ for exponentially damped harmonic oscillations is superior to conventional Hilbert transform method. The ‘true envelope’ of free decaying strain signals calculated from the Hilbert-twin method yields excellent estimation of the logarithmic decrement in metals, alloys, and solids.

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Mechanical Spectroscopy of Hyperstabilized Martensites

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.184.355 ◽

2012 ◽

Vol 184 ◽

pp. 355-360 ◽

Cited By ~ 6

Author(s):

Sergey Kustov ◽

R. Santamarta ◽

E. Cesari ◽

K. Sapozhnikov ◽

V. Nikolaev ◽

...

Keyword(s):

Martensitic Transformation ◽

Internal Friction ◽

Essential Role ◽

Parent Phase ◽

Martensitic Transformation Temperature ◽

Mechanical Spectroscopy ◽

Internal Friction Peak ◽

Pinning Effect ◽

The One

The internal friction of the hyperstabilized martensite demonstrates very low values, both above and below the nominal martensitic transformation temperature, due to a pronounced pinning effect. Over a wide temperature range it is comparable with the level of damping in the parent phase. A study of the temperature dependence of the non-linear ultrasonic internal friction and its strain amplitude hysteresis indicates that the diffusion, assisted by dislocations/interfaces, is quite pronounced and in Ni-Fe-Ga and Cu-Al-Be alloys it operates at temperatures around 20 K. The renucleation of the lamellar parent phase during the reverse martensitic transformation close to 600 K is accompanied by an internal friction peak which demonstrates a substantial transitory contribution. After renucleation of the parent phase the samples recover a conventional martensitic transformation with the internal friction level in the martensite comparable to the one in non-stabilized samples. Observations of a relaxation peak in the parent phase of different alloys for temperatures just below the renucleation stage of the reverse transformation point to the essential role of diffusion in the nucleation of the parent phase in hyperstabilized martensites.

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Internal friction and mechanical spectroscopy of metals and alloys

Metal Science and Heat Treatment ◽

10.1007/s11041-012-9482-7 ◽

2012 ◽

Vol 54 (5-6) ◽

pp. 207-207

Keyword(s):

Internal Friction ◽

Metals And Alloys ◽

Mechanical Spectroscopy

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Study on the Granular Shear Strength Parameters of Dumping Site

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.358 ◽

2012 ◽

Vol 256-259 ◽

pp. 358-361

Author(s):

Xiang Yun Kong ◽

Guang Jin Wang ◽

Xiao Chao Zhou

Keyword(s):

Particle Size ◽

Grain Size ◽

Shear Strength ◽

Internal Friction ◽

Friction Angle ◽

Internal Friction Angle ◽

Shear Strength Parameters ◽

Strength Parameters ◽

Dumping Site ◽

Size Grading

Apparent particle size grading is the important characteristic of super-high bench dumping site, and the critical factors with the impact of its stability and disaster prevention are the fragmentation distribution and shear strength parameters of granular. With the copper mine dumping site which had the feature of apparent particle size grading, the thesis carried out the study of on-site particle size investigation and indoor laboratory. The particle-size distribution law with the changing of dumping-site height was analyzed and quantitative relationship between the fragmentation distribution and shear strength parameters of granular was discussed. The research results indicated that coarse-grain contents and maximum grain size were increased significantly according to the decreasing of dumping-site height, which showed that the dumping-site had the feature of apparent particle size grading. The coarse particle content in the grain size composition and internal friction angle φ of shear strength parameters increased with the obvious increment of the distribution value B. The relationship between distribution value B and the internal friction angle φ could be expressed by exponential function curve.

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