Indentation Technique to Investigate Elastic Moduli of Thin Films on Substrates

1988 ◽  
Vol 130 ◽  
Author(s):  
D. S. Stone ◽  
T. W. Wu ◽  
P.-S. Alexopoulos ◽  
W. R. Lafontaine
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Thin Films ◽  
Closed Form ◽  
Elastic Moduli ◽  
Depth Sensing ◽  
Indentation Technique ◽  
Average Displacement ◽  
Elasticity Solutions ◽  
Poor Adhesion

AbstractClosed-form elasticity solutions are introduced, that predict the average displacement beneath square and triangular, uniformly loaded areas at the surface of a bilayer. The solutions aid in the application of depth-sensing indentation techniques for measuring thin film elastic moduli. The elasticity solutions agree closely with experimental data of Al, Si, 1 μm Al on Si, and 2 μm Cr on Si. The case of poor adhesion between the film and substrate is briefly examined.

The Elastic Moduli of Silver Thin Films Measured with a New Microtensile Tester

1991 ◽  
Vol 239 ◽  
Author(s):  
J. Ruud ◽  
D. Josell ◽  
A. L. Greer ◽  
F. Spaepen
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Diffraction Grating ◽  
Strain Measurement ◽  
Elastic Moduli ◽  
Two Dimensional ◽  
Bulk Crystals ◽  
Free Standing ◽  
Tensile Direction ◽  
Silver Thin Films

ABSTRACTA new design for a thin film microtensile tester is presented. The strain is measured directly on the free-standing thin film from the displacement of laser spots diffracted from a thin grating applied to its surface by photolithography. The diffraction grating is two-dimensional, allowing strain measurement both along and transverse to the tensile direction. In principle, both Young's modulus and Poisson's ratio of a thin film can be determined. Ag thin films with strong <111> texture were tested. The measured Young moduli agreed with those measured on bulk crystals, but the measured Poisson ratios were low, most likely due to slight transverse folding of the film that developed during the test.

A Novel Technique to Determine Elastic Constants of Thin Films

2008 ◽  
Vol 1139 ◽  
Author(s):  
Klaus Martinschitz ◽  
Rostislav Daniel ◽  
Christian Mitterer ◽  
Keckes Jozef
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Elastic Moduli ◽  
Elastic Anisotropy ◽  
Interaction Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Anisotropic Factor ◽  
Polycrystalline Thin Films ◽  
Cu Thin Film

AbstractA new X-ray diffraction technique to determine elastic moduli of polycrystalline thin films deposited on monocrystalline substrates is demonstrated. The technique is based on the combination of sin2ψ and X-ray diffraction wafer curvature techniques which are used to characterize X-ray elastic strains and macroscopic stress in thin film. The strain measurements must be performed for various hkl reflections. The stresses are determined from the substrate curvature applying the Stoney's equation. The stress and strain values are used to calculate hkl reflection dependent X-ray elastic moduli. The mechanical elastic moduli can be then extrapolated from X-ray elastic moduli considering film macroscopic elastic anisotropy. The derived approach shows for which reflection and corresponding value of the X-ray anisotropic factor Γ the X-ray elastic moduli are equal to their mechanical counterparts in the case of fibre textured cubic polycrystalline aggregates. The approach is independent of the crystal elastic anisotropy and depends on the fibre texture type, the texture sharpness, the amount of randomly oriented crystallites and on the supposed grain interaction model. The new method is demonstrated on a fiber textured Cu thin film deposited on monocrystalline Si(100) substrate. The advantage of the new technique remains in the fact that moduli are determined non-destructively, using a static diffraction experiment and represent volume averaged quantities.

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>

Calculation of Intrinsic Stresses and Elastic Moduli in Nonhomogeneous Thin Films

2000 ◽  
Vol 653 ◽  
Author(s):  
Pedro C. Andia ◽  
Francesco Costanzo ◽  
Gary L. Gray ◽  
Thomas J. Yurick
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Residual Stresses ◽  
Computer Simulations ◽  
System Application ◽  
Elastic Moduli ◽  
Particle System ◽  
Particle Systems

AbstractAn approach is presented for the determination of the residual stresses and elastic moduli of particle systems resulting from computer simulations of particle or atomic deposition. The proposed technique is based on fundamental concepts of elasticity and is capable of capturing the variation of stresses and moduli as functions of position within the system. Application to a simple particle system consisting of a deposited thin film is demonstrated.

Elasticity Analysis to Aid in Extracting Thin Film Elastic Moduli From Continuous Indentation Data

1990 ◽  
Vol 112 (1) ◽  
pp. 41-46 ◽  
Author(s):  
D. S. Stone
Keyword(s):  
Thin Film ◽  
Elastic Moduli ◽  
Small Computer ◽  
Elasticity Analysis ◽  
Sodium Borosilicate Glass ◽  
Projected Area ◽  
Elasticity Solutions ◽  
Unloading Compliance ◽  
Continuous Indentation

This article provides elasticity solutions to the indentation of a bilayer by three-sided and four-sided indentors. These solutions aid characterization of thin film elastic moduli through continuous indentation techniques. The solutions are expressed in closed-form, and can be numerically evaluated on a small computer; additionally, graphs of some of the solutions are provided to aid in rapid data analysis. Simulations of unloading compliance, C, versus 1/A1/2 (A = projected area of indent) are compared with experimental data. The data are taken from measurements of single crystal Si, polycrystalline Al, and 1 μm Al deposited on Si. The elasticity analysis is used in the measurement of the elastic modulus of a sodium borosilicate glass, and the same glass but with a damaged surface layer introduced by suspension in an acid solution.

An Improvement of the Doerner-Nix Function for Substrate Effects in Ultrathin Films

2008 ◽  
Vol 1086 ◽  
Author(s):  
BO Zhou ◽  
Barton C Prorok
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Thin Films ◽  
Ultrathin Films ◽  
Early Stage ◽  
Displacement Curve ◽  
Substrate Effects ◽  
Amorphous Thin Films ◽  
Continuous Stiffness Measurement ◽  
Hard Substrates

AbstractSubstrate effects continue to be the key issue in interrogating thin films by nanoindentation. In this study, we studies amorphous thin films of several different materials deposited onto a silicon wafer. These materials span from being considerable softer than the substrate to films significantly harder than the substrate. The thin film Young's modulus Ef was measured with a MTS Nanoindenter XP system using the continuous stiffness measurement (CSM). The so-called “flat region” was observed in the early stage of nearly every CSM modulus-displacement curve for all materials studied. The depth of this region (hcr) was found to vary with the material. Based on the experimental data, we were able to modify the Doerner & Nix model for thin film indentation on a substrate, particularly their parameter alpha (α). The modified relation was found to be adept at closely matching all experimental data collected, which spanned both soft films on hard substrates and hard films on soft substrates.

A new procedure for measuring the decohesion energy for thin ductile films on substrates

1994 ◽  
Vol 9 (7) ◽  
pp. 1734-1741 ◽  
Author(s):  
A. Bagchi ◽  
G.E. Lucas ◽  
Z. Suo ◽  
A.G. Evans
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Fracture Resistance ◽  
Strain Energy ◽  
Critical Thickness ◽  
Interfacial Fracture ◽  
Intrinsic Stress ◽  
Testing Technique ◽  
Subsequent Processing ◽  
Elasticity Solutions

A novel testing technique has been developed capable of measuring the interfacial fracture resistance, Γi, of thin ductile films on substrates. In this technique, the thin film on the substrate is stressed by depositing onto the film a second superlayer of material, having a large intrinsic stress, such as Cr. Subsequent processing defines a precrack at the interface between the film and the substrate. The strain energy available for driving the debond crack is modulated by varying the thickness of the Cr superlayer. Spontaneous decohesion occurs for superlayers exceeding a critical thickness. The latter is used to obtain Γi from elasticity solutions for residually stressed thin films. The technique has been demonstrated for Cu thin films on silica substrates.

Characterizing the Modulus and Hardness of Photopatternable Silicone Compositions Using Depth Sensing Nanoindentation

2003 ◽  
Vol 769 ◽  
Author(s):  
Brian R. Harkness ◽  
Richard L. Schalek ◽  
Satyen K. Sarmah ◽  
Lawrence T. Drzal
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Mechanical Properties ◽  
Sample Surface ◽  
Bulk Sample ◽  
Microelectronic Device ◽  
Depth Sensing ◽  
Device Integration ◽  
Low Modulus ◽  
Thin Film Dielectrics

AbstractThe mechanical properties of two cured silicone monolithic specimens with targeted bulk moduli of 300 and 10 MPa have been evaluated by DMA and regionally by CSM nanoindentation. The results showed that the mechanical properties of the monolithic samples were heterogeneous, with the DMA and nanoindention results only in agreement at the midplane of cleaved bulk samples. The specimens showed a significantly higher modulus at the sample surfaces compared to the bulk. Thin films of the same silicones displayed a modulus closer to that of the bulk sample surface. The nanoindentation results of this study were reliable and consistent, and are being used to assess the effects of material and microelectronic device integration processes on the mechanical properties of a series of low modulus photopatternable silicone thin film dielectrics.

A simple method for evaluating elastic modulus of thin films by nanoindentation

2009 ◽  
Vol 24 (3) ◽  
pp. 801-815 ◽  
Author(s):  
Zhongxin Wei ◽  
Guoping Zhang ◽  
Hao Chen ◽  
Jian Luo ◽  
Ranran Liu ◽  
...  
Keyword(s):  
Experimental Data ◽  
Thin Films ◽  
Elastic Moduli ◽  
Empirical Method ◽  
Published Data ◽  
Simple Method ◽  
Wide Range ◽  
Standard Values ◽  
Film Substrate ◽  
Design Experiments

A simple empirical method that extracts the elastic moduli of both thin films and the underlying substrates is proposed and validated by both new nanoindentation experiments and published data. Deconvolution of thin film’s elastic properties from the substrate is achieved by statistical estimation, where a simple function relating the elastic moduli of the thin film and substrate to the film-substrate composite modulus is used to fit the experimental data plotted against the logarithmic indentation depth normalized by film thickness. Experimental data from a wide range of soft and hard films on substrate were used to demonstrate the deconvolution and validate the method. The estimated elastic moduli of thin films and substrates agree well with their corresponding standard values or values obtained by other methods. The advantages of this method are discussed, and recommendations are made on how to design experiments to obtain reliable data for this method.

Radiative Properties of Superconducting Y-Ba-Cu-O Thin Films

1991 ◽  
Vol 113 (2) ◽  
pp. 487-493 ◽  
Author(s):  
P. E. Phelan ◽  
M. I. Flik ◽  
C. L. Tien
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Thin Films ◽  
High Temperature ◽  
Superconducting State ◽  
High Temperature Superconductors ◽  
Radiation Shielding ◽  
Radiative Properties ◽  
Quantum Mechanical ◽  
London Theory

Some applications of thin-film high-temperature superconductors, such as bolometers, radiation shielding, and space-cooled electronics, require knowledge of the superconducting-state radiative properties. At present, no general predictive model of the radiative properties has been presented. In this work, reflectance predictions based on two of the major theories of the superconducting state, the classical Drude–London theory and the quantum-mechanical Mattis–Bardeen theory, are compared with the available experimental data to determine the best method for predicting the radiative properties of thin-film Y-Ba-Cu-O. It is seen that the Mattis–Bardeen theory is more successful than the Drude–London theory in predicting the reflectance. Consequently, approximate formulae for the Mattis–Bardeen theory are developed, thus enhancing the theory’s usefulness for engineering calculations.

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