Effects of mechanical properties, residual stress and indenter tip geometry on instrumented indentation data in thin films

The instrumented indentation technique (IIT) is a novel method for evaluating mechanical properties such as tensile properties, toughness and residual stress by analyzing the indentation load-depth curve measured during indentation. It can be applied directly on small-scale and localized sections in industrial structures and structural components since specimen preparation is very easy and the experimental procedure is nondestructive. We introduce the principles for measuring mechanical properties with IIT: tensile properties by using a representative stress and strain approach, residual stress by analyzing the stress-free and stressed-state indentation curves, and fracture toughness of metals based on a ductile or brittle model according to the fracture behavior of the material. The experimental results from IIT were verified by comparing results from conventional methods such as uniaxial tensile testing for tensile properties, mechanical saw-cutting and hole-drilling methods for residual stress, and CTOD test for fracture toughness.

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Research on some Key Mechanical Properties of Silicon Nitride Thin Films Deposited by PECVD

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.742.773 ◽

2015 ◽

Vol 742 ◽

pp. 773-777

Author(s):

Qun Feng Yang ◽

Jian Yi Zheng ◽

Jun Qing Wang ◽

Jun Hui Lin ◽

Xue Nan Zhao ◽

...

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Residual Stress ◽

Silicon Nitride ◽

Mechanical Characteristics ◽

Dielectric Films ◽

Rotating Beam ◽

Atomic Force ◽

Scanning Electron

The purpose of this work is to study the mechanical characteristics of the silicon nitride(SiNx) thin films prepared by PECVD technique, some researches as follows were carried out. First, the SiNx thin films were deposited on the two different substrates. Then, the atomic force microscope (AFM) was adopted to test the surface quality of the SiNxfilms, and the scanning electron microscope (SEM) was used to test the section morphology of the SiNxthin films. Finally, the rotating beam structures was applied to measure the residual stress in the SiNx films. The SiNxthin films with low stress can be fabricated through PECVD, in which the surface roughness values(Ra) are 1.261 nm and 2.383nm, and the residual stress is 43.5 kPa. Therefore, the SiNxthin films deposited by PECVD are suitable for the preparation of device dielectric films in MEMS.

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Influence of residual stress on mechanical properties of TiAlN thin films

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2012.05.108 ◽

2013 ◽

Vol 228 ◽

pp. S328-S330 ◽

Cited By ~ 16

Author(s):

Guo-an Cheng ◽

Dong-yan Han ◽

Chang-lin Liang ◽

Xiao-ling Wu ◽

Rui-ting Zheng

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Residual Stress

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Measuring the elastic modulus and residual stress of freestanding thin films using nanoindentation techniques

Journal of Materials Research ◽

10.1557/jmr.2009.0360 ◽

2009 ◽

Vol 24 (9) ◽

pp. 2974-2985 ◽

Cited By ~ 14

Author(s):

Erik G. Herbert ◽

Warren C. Oliver ◽

Maarten P. de Boer ◽

George M. Pharr

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Residual Stress ◽

Thermal Expansion ◽

Elastic Modulus ◽

Dimensional Analysis ◽

Experimental Verification ◽

Cu Films ◽

Proposed Model ◽

The Difference

A new method is proposed to determine the elastic modulus and residual stress of freestanding thin films based on nanoindentation techniques. The experimentally measured stiffness-displacement response is applied to a simple membrane model that assumes the film deformation is dominated by stretching as opposed to bending. Dimensional analysis is used to identify appropriate limitations of the proposed model. Experimental verification of the method is demonstrated for Al/0.5 wt% Cu films nominally 22 µm wide, 0.55 µm thick, and 150, 300, and 500 µm long. The estimated modulus for the four freestanding films match the value measured by electrostatic techniques to within 2%, and the residual stress to within 19.1%. The difference in residual stress can be completely accounted for by thermal expansion and a modest change in temperature of 3 °C. Numerous experimental pitfalls are identified and discussed. Collectively, these data and the technique used to generate them should help future investigators make more accurate and precise measurements of the mechanical properties of freestanding thin films using nanoindentation.

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Influence of Support Compliance and Residual Stress on the Shape of Doubly-Supported Surface-Micromachined Beams

10.1115/imece1999-0238 ◽

1999 ◽

Author(s):

Mauro J. Kobrinsky ◽

Erik R. Deutsch ◽

Stephen D. Senturia

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Finite Element Method ◽

Residual Stress ◽

Gradual Increase ◽

The Other ◽

Elastic Model ◽

Dimensional Model ◽

Stable States ◽

One Dimensional

Abstract Doubly-supported surface-micromachined beams are increasingly used to study the mechanical properties of thin films. Residual stresses in the beams cause significant vertical deflections, which affect the performance of these devices. We present here both experimental results for doubly-supported polysilicon surface-micromachined beams, and an elastic model of the devices that takes into account the compliance of the supports and the geometrical non-linear dependence of the vertical deflections on the stress in the beam. An elastic one-dimensional model was used for the beams, and the response of the supports to forces and moments was obtained using Finite Element Method simulations. The model explains a previously observed gradual increase of the maximum vertical deflections of the beams with increasing length at a given constant residual stress, and, in agreement with experimental observations, predicts two stable states for compressively stressed beams: one with the beam bent up, the other down.

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Application of Instrumented Indentation Technique for Small Scale Testing

Volume 6: Materials and Fabrication ◽

10.1115/pvp2007-26056 ◽

2007 ◽

Author(s):

Kug-Hwan Kim ◽

Kyung-Woo Lee ◽

Ju-Young Kim ◽

Dongil Kwon ◽

Kwang-Ho Kim

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Residual Stress ◽

Tensile Properties ◽

Pressure Vessel ◽

Uniaxial Tensile ◽

Small Scale ◽

Uniaxial Tensile Test ◽

Instrumented Indentation ◽

Indentation Technique

Instrumented indentation technique (IIT) is a novel tool to estimate mechanical properties such as tensile properties, residual stress and fracture toughness by analyzing indentation load-depth curve measured during loading-unloading of indentation. It can be applied directly in small-scale and localized sections of pressure vessel and pipeline since the preparation of specimen is very easy and the experimental procedure is feasible and nondestructive. We present the principles developed for measuring mechanical properties using IIT; the tensile properties by defining the representative stress and strain underneath a spherical indenter, the residual stress near the weldments using the stress-insensitive contact hardness model, and the fracture toughness of ductile metal based on critical indentation energy model. The experimental results from IIT were verified by comparing the results from the conventional methods such as uniaxial tensile test for tensile properties, mechanical saw-cutting and hole-drilling methods for residual stress, and CTOD test for fracture toughness. In particular, the applications of IIT in small scale materials and localized sections of the pressure vessel and pipeline in-use and in-fields are presented.

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Evolution of Principle and Practice of Electrodeposited Thin Film: A Review on Effect of Temperature and Sonication

International Journal of Electrochemistry ◽

10.4061/2011/568023 ◽

2011 ◽

Vol 2011 ◽

pp. 1-16 ◽

Cited By ~ 8

Author(s):

A. Mallik ◽

B. C. Ray

Keyword(s):

Thin Film ◽

Thin Films ◽

Mechanical Properties ◽

Residual Stress ◽

Electrochemical Deposition ◽

Surface Engineering ◽

Effect Of Temperature ◽

Structure And Morphology ◽

Nucleation Mechanisms ◽

Effects Of Temperature

This review discusses briefly the important aspects of thin films. The introduction of the article is a summary of evolution of thin films from surface engineering, their deposition methods, and important issues. The fundamental aspects of electrochemical deposition with special emphasis on the effect of temperature on the phase formation have been reviewed briefly. The field of sonoelectrochemistry has been discussed in the paper. The literature regarding the effects of temperature and sonication on the structure and morphology of the deposits and nucleation mechanisms, residual stress, and mechanical properties has also been covered briefly.

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Residual stress measurements and mechanical properties of AlN thin films as ultra-sensitive materials for nanoelectromechanical systems

The Philosophical Magazine A Journal of Theoretical Experimental and Applied Physics ◽

10.1080/14786435.2012.669074 ◽

2012 ◽

Vol 92 (25-27) ◽

pp. 3392-3401 ◽

Cited By ~ 3

Author(s):

R. Grieseler ◽

J. Klaus ◽

M. Stubenrauch ◽

K. Tonisch ◽

S. Michael ◽

...

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Residual Stress ◽

Nanoelectromechanical Systems ◽

Stress Measurements

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Effect of Annealing on Microstructure and Mechanical Properties of Magnetron Sputtered Cu Thin Films

Advances in Materials Science and Engineering ◽

10.1155/2015/969580 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 16

Author(s):

Shiwen Du ◽

Yongtang Li

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Residual Stress ◽

Grain Size ◽

Strain Energy ◽

Texture Coefficient ◽

Elastic Strain Energy ◽

Interface Energy ◽

Cu Films ◽

Si Substrates

Cu thin films were deposited on Si substrates using direct current (DC) magnetron sputtering. Microstructure evolution and mechanical properties of Cu thin films with different annealing temperatures were investigated by atomic force microscopy (AFM), X-ray diffraction (XRD), and nanoindentation. The surface morphology, roughness, and grain size of the Cu films were characterized by AFM. The minimization of energy including surface energy, interface energy, and strain energy (elastic strain energy and plastic strain energy) controlled the microstructural evolution. A classical Hall-Petch relationship was exhibited between the yield stress and grain size. The residual stress depended on crystal orientation. The residual stress as-deposited was of tension and decreased with decreasing of (111) orientation. The ratio of texture coefficient of (111)/(220) can be used as a merit for the state of residual stress.

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