scholarly journals SMART transfer method to directly compare the mechanical response of water-supported and free-standing ultrathin polymeric films

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Luke A. Galuska ◽  
Eric S. Muckley ◽  
Zhiqiang Cao ◽  
Dakota F. Ehlenberg ◽  
Zhiyuan Qian ◽  
...  
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Quartz Crystal ◽  
Mechanical Response ◽  
Polymeric Films ◽  
Free Standing ◽  
Transfer Method ◽  
Shear Motion ◽  
Main Component

AbstractIntrinsic mechanical properties of sub-100 nm thin films are markedly difficult to obtain, yet an ever-growing necessity for emerging fields such as soft organic electronics. To complicate matters, the interfacial contribution plays a major role in such thin films and is often unexplored despite supporting substrates being a main component in current metrologies. Here we present the shear motion assisted robust transfer technique for fabricating free-standing sub-100 nm films and measuring their inherent structural–mechanical properties. We compare these results to water-supported measurements, exploring two phenomena: 1) The influence of confinement on mechanics and 2) the role of water on the mechanical properties of hydrophobic films. Upon confinement, polystyrene films exhibit increased strain at failure, and reduced yield stress, while modulus is reduced only for the thinnest 19 nm film. Water measurements demonstrate subtle differences in mechanics which we elucidate using quartz crystal microbalance and neutron reflectometry.

Mechanical Properties of Al Thin Films as Measured by Bulge Testing

1999 ◽  
Vol 594 ◽  
Author(s):  
Yinmin Wang ◽  
Richard L. Edwards ◽  
Kevin J. Hemker
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Mechanical Response ◽  
Plastic Behavior ◽  
Free Standing ◽  
Stress Strain ◽  
Bulge Testing ◽  
Deformation Regime ◽  
Von Mises ◽  
Equivalent Yield

AbstractFree-standing rectangular Al thin films have been fabricated using sputter deposition and standard micromachining techniques. Mechanical properties and residual stresses of both asdeposited and annealed Al films were measured by bulge testing. The films were loaded into the plastic deformation regime, and then unloaded and reloaded several times. The pressure and deflection of the thin films were recorded and used to generate stress-strain curves. The planestrain elastic modulus, flow stress and plastic behavior of the Al thin films were used to characterize the mechanical response of these films. The Al films were measured to have a plane-strain modulus that is slightly lower than the literature values for a {111} textured film. The Von-Mises equivalent yield stress was measured to be higher in the annealed films but much more significant strain hardening was observed in the as-deposited films. A plastic hysteresis was observed on unloading and reloading stress-strain curves of the as-deposited Al films but not the annealed films.

Effects of dynamic indentation on the mechanical response of materials

2008 ◽  
Vol 23 (6) ◽  
pp. 1604-1613 ◽  
Author(s):  
M.J. Cordill ◽  
N.R. Moody ◽  
W.W. Gerberich
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Mechanical Response ◽  
Length Scale ◽  
Polycrystalline Nickel ◽  
Dynamic Indentation ◽  
Crystalline Materials ◽  
Fused Quartz ◽  
Hardness Values ◽  
Measured Hardness

Dynamic indentation techniques are often used to determine mechanical properties as a function of depth by continuously measuring the stiffness of a material. The dynamics are used by superimposing an oscillation on top of the monotonic loading. Of interest was how the oscillation affects the measured mechanical properties when compared to a quasi-static indent run at the same loading conditions as a dynamic. Single crystals of nickel and NaCl as well as a polycrystalline nickel sample and amorphous fused quartz and polycarbonate have all been studied. With respect to dynamic oscillations, the result is a decrease of the load at the same displacement and thus lower measured hardness values of the ductile crystalline materials. It has also been found that the first 100 nm of displacement are the most affected by the oscillating tip, an important length scale for testing thin films, nanopillars, and nanoparticles.

Characterization of Thin Organic and Polymeric Films by Spectroscopic Methods

MRS Bulletin ◽  
1987 ◽  
Vol 12 (8) ◽  
pp. 39-41 ◽  
Author(s):  
J.F. Rabolt
Keyword(s):  
Thin Films ◽  
Structural Integrity ◽  
Materials Science ◽  
Molecular Level ◽  
Polymeric Films ◽  
Organic Films ◽  
Semiconductor Films ◽  
Intimate Contact ◽  
The Individual

Much of the anisotropic mechanical and thermal behavior exhibited by materials can be attributed to anisotropic orientation at the molecular level. In self-supporting thin films (5–10 microns) and those (0.01–1.0 microns) deposited on solid substrates, the role of molecular orientation is even more important since it will critically determine their two-dimensional behavior and their structural integrity as well. These two aspects are extremely important because if thin organic and polymeric films are to be competitive with existing materials for such diverse applications1 as chemical sensors and integrated optics, they must be mechanically robust and, ideally, defect free. These stringent constraints dictate that sophisticated characterization techniques, which can interrogate at the molecular level, be developed or refined so as to have the sensitivity to address these critical issues.The development of nondestructive techniques for studying thin organic films has certainly lagged behind those developed for metallic and semiconductor films. Unfortunately, many of these same techniques cannot be simply applied to organic films because they are “invasive” and often alter the structure of the system they were designed to probe. This is especially so in organic and polymer films, and this awareness within the materials science community has led to the adaptation of many photon intensive techniques to the study of thin films. A number of these will be discussed in later sections with their relative merit put in perspective.Certainly the origins of anisotropic structure in bulk materials are manyfold, but the spatial constraints in 2-D can lead to even more complex causes of orientation. In thin films on substrates the role of the surface is important in determining the ordering and orientation of the individual molecular segments which come into intimate contact with it. The extent of this orientation and order is still somewhat controversial but there is general agreement that it probably differs depending on the nature of the substrate.

scholarly journals A Direct Comparison of Three Buckling-Based Methods to Measure the Elastic Modulus of Nanobiocomposite Thin Films

2020 ◽  
Author(s):  
Taylor C. Stimpson ◽  
Daniel A. Osorio ◽  
Emily D. Cranston ◽  
Jose Moran-Mirabal
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Elastic Modulus ◽  
Elastic Moduli ◽  
Input Parameter ◽  
Layer By Layer ◽  
Free Standing ◽  
Film Composition ◽  
Parameter Values

<p>To engineer tunable thin film materials, accurate measurement of their mechanical properties is crucial. However, characterizing the elastic modulus with current methods is particularly challenging for sub-micrometer thick films and hygroscopic materials because they are highly sensitive to environmental conditions and most methods require free-standing films which are difficult to prepare. In this work, we directly compared three buckling-based methods to determine the elastic moduli of supported thin films: 1) biaxial thermal shrinking, 2) uniaxial thermal shrinking, and 3) the mechanically compressed, strain-induced elastic buckling instability for mechanical measurements (SIEBIMM) method. Nanobiocomposite model films composed of cellulose nanocrystals (CNCs) and polyethyleneimine (PEI) were assembled using layer-by-layer deposition to control composition and thickness. The three buckling-based methods yielded the same trends and comparable values for the elastic moduli of each CNC-PEI film composition (ranging from 15 – 44 GPa, depending on film composition). This suggests that the methods are similarly effective for the quantification of thin film mechanical properties. Increasing the CNC content in the films statistically increased the modulus, however, increasing the PEI content did not lead to significant changes. The standard deviation of elastic moduli determined from SIEBIMM was 2-4 times larger than for thermal shrinking, likely due to extensive cracking and partial film delamination. In light of these results, biaxial thermal shrinking is recommended as the method of choice because it affords the simplest implementation and analysis and is the least sensitive to small deviations in the input parameter values, such as film thickness or substrate modulus.</p>

scholarly journals Tuning Nanoscale Friction by Applying Weak Magnetic Fields to Reorient Adsorbed Oxygen Molecules

2018 ◽  
Vol 4 (1) ◽  
pp. 1 ◽  
Author(s):  
Z. Fredricks ◽  
K. Stevens ◽  
S. Kenny ◽  
B. Acharya ◽  
J. Krim
Keyword(s):  
Magnetic Field ◽  
Thin Films ◽  
Weak Magnetic Field ◽  
Quartz Crystal ◽  
Sliding Friction ◽  
Model Systems ◽  
Theoretical Studies ◽  
Weak Magnetic Fields ◽  
Gold Substrates

Sliding friction levels of thin (1–2 monolayers) and thick (~10 monolayers) oxygen films adsorbed on nickel and gold at 47.5 K have been measured by means of a quartz crystal microbalance (QCM) technique. Friction levels for the thin (thick) films on nickel in the presence of a weak magnetic field were observed to be approximately 30% (50%) lower than those recorded in the absence of the external field. Friction levels for thin films on gold were meanwhile observed to be substantially increased in the presence of the field. Magnetically-induced structural reorientation (magnetostriction) and/or realignment of adlayer spins, which respectively reduce structural and magnetic interfacial corrugation and commensurability, appear likely mechanisms underlying the observed field-induced reductions in friction for the nickel samples. Eddy current formation in the gold substrates may account for the increased friction levels in this system. The work demonstrates the role of magnetic effects in model systems that are highly amenable to theoretical studies and modeling.

scholarly journals Local dynamic mechanical properties in model free-standing polymer thin films

2005 ◽  
Vol 122 (14) ◽  
pp. 144712 ◽  
Author(s):  
Kenji Yoshimoto ◽  
Tushar S. Jain ◽  
Paul F. Nealey ◽  
Juan J. de Pablo
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Polymer Thin Films ◽  
Dynamic Mechanical Properties ◽  
Local Dynamic ◽  
Free Standing ◽  
Dynamic Mechanical ◽  
Model Free

scholarly journals Structure, stress, and mechanical properties of Mo-Al-N thin films deposited by dc reactive magnetron cosputtering: Role of point defects

2020 ◽  
Vol 38 (5) ◽  
pp. 053401 ◽  
Author(s):  
Fırat Anğay ◽  
Lukas Löfler ◽  
Florent Tetard ◽  
Dominique Eyidi ◽  
Philippe Djemia ◽  
...  
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Point Defects ◽  
Reactive Magnetron

Hardness and Young's modulus of amorphous a-SiC thin films determined by nanoindentation and bulge tests

1994 ◽  
Vol 9 (1) ◽  
pp. 96-103 ◽  
Author(s):  
M.A. El Khakani ◽  
M. Chaker ◽  
A. Jean ◽  
S. Boily ◽  
J.C. Kieffer ◽  
...  
Keyword(s):  
Thin Films ◽  
Mechanical Properties ◽  
Silicon Carbide ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Chemical Vapor ◽  
Free Standing ◽  
Film Composition ◽  
Sputtering Deposition ◽  
Sic Films

Due to its interesting mechanical properties, silicon carbide is an excellent material for many applications. In this paper, we report on the mechanical properties of amorphous hydrogenated or hydrogen-free silicon carbide thin films deposited by using different deposition techniques, namely plasma enhanced chemical vapor deposition (PECVD), laser ablation deposition (LAD), and triode sputtering deposition (TSD). a-SixC1−x: H PECVD, a-SiC LAD, and a-SiC TSD thin films and corresponding free-standing membranes were mechanically investigated by using nanoindentation and bulge techniques, respectively. Hardness (H), Young's modulus (E), and Poisson's ratio (v) of the studied silicon carbide thin films were determined. It is shown that for hydrogenated a-SixC1−x: H PECVD films, both hardness and Young's modulus are dependent on the film composition. The nearly stoichiometric a-SiC: H films present higher H and E values than the Si-rich a-SixC1−x: H films. For hydrogen-free a-SiC films, the hardness and Young's modulus were as high as about 30 GPa and 240 GPa, respectively. Hydrogen-free a-SiC films present both hardness and Young's modulus values higher by about 50% than those of hydrogenated a-SiC: H PECVD films. By using the FTIR absorption spectroscopy, we estimated the Si-C bond densities (NSiC) from the Si-C stretching absorption band (centered around 780 cm−1), and were thus able to correlate the observed mechanical behavior of a-SiC films to their microstructure. We indeed point out a constant-plus-linear variation of the hardness and Young's modulus upon the Si-C bond density, over the NSiC investigated range [(4–18) × 1022 bond · cm−3], regardless of the film composition or the deposition technique.

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