A Novel Method for Determining Poisson's Ratio of Thin Film Materials Using Ultra-Wide Micromachined Bilayer Cantilevers

2004 ◽  
Vol 20 (2) ◽  
pp. 107-112
Author(s):  
Max Ti-Kuang Hou ◽  
Rongshun Chen
Keyword(s):  
Thin Film ◽  
Material Properties ◽  
Poisson’S Ratio ◽  
Plate Theory ◽  
Poisson's Ratio ◽  
Film Material ◽  
Thin Film Material ◽  
Needed Information ◽  
Before And After ◽  
Novel Method

AbstractNarrow micromachined bilayer cantilevers, which are broadly used to determine different thin film material properties, have rarely been used to characterize the Poisson's ratio. It is difficult to be determined from the tip deflection, and thus the Poisson's ratio, of the narrow bilayer cantilever. In this paper, the tip deflections of ultra-wide micromachined bilayer cantilevers carry the needed information for finding the Poisson's ratio of thin-film materials. The measurement process and its corresponding model, based on the plate theory, is introduced and tested. The Poisson's ratio of the thin film is determined by comparing the tip deflections of the bilayer cantilever before and after the deposition of the upper layer. Because the fabrication processes are widely used in surface micromachining, the method can be easily implemented.

scholarly journals Application-specific oxide-based and metal-dielectric thin-film materials prepared by RF sputtering

2019 ◽  
Author(s):  
Mohammad Nur E Alam ◽  
Mikhail Vasiliev
Keyword(s):  
Thin Film ◽  
Material Properties ◽  
High Performance ◽  
Rf Sputtering ◽  
Rf Magnetron Sputtering ◽  
Film Material ◽  
Dielectric Thin Film ◽  
Thin Film Material ◽  
Material Systems ◽  
Application Specific

We report on the development of several different thin-film material systems prepared by RF magnetron sputtering at Edith Cowan University nanofabrication labs. While focusing on the RF sputtering process optimizations for new or the previously underexplored material compositions and multilayer structures, we disclose several unforeseen material properties and behaviours. We communicate research results related to the design, prototyping, and practical fabrication of high-performance magneto-optic (MO) materials, oxide based sensor components, and transparent heat regulation coatings for advanced construction and solar windows.

Abnormal infrared effects of nanometer scale thin film material of PtPd alloy in CO adsorption

2001 ◽  
Vol 46 (17) ◽  
pp. 1439-1442 ◽  
Author(s):  
Zhi Chen ◽  
Shigang Sun ◽  
Nan Ding ◽  
Zhiyou Zhou
Keyword(s):  
Thin Film ◽  
Co Adsorption ◽  
Nanometer Scale ◽  
Film Material ◽  
Thin Film Material

Preparation and Characterization of SnO2/WO3/MWCNT Nanocomposite Thin Film for NO2 Gas Sensor

2010 ◽  
Vol 129-131 ◽  
pp. 99-103
Author(s):  
Wei Lin ◽  
Shi Zhen Huang ◽  
Wen Zhe Chen
Keyword(s):  
Thin Film ◽  
Gas Sensor ◽  
Photoelectron Spectroscopy ◽  
Mixed Oxides ◽  
Surface Composition ◽  
Chemical Elements ◽  
Film Material ◽  
Nanocomposite Thin Film ◽  
Oxide Compound ◽  
Thin Film Material

A novel nanocomposite thin film material of SnO2/WO3 metal oxide compound doped by multi-walled carbon nanotubes (MWCNT) and its corresponding gas sensor were prepared by radio frequency (RF) reactive magnetron sputtering. The surface composition and chemical elements of the thin film material were respectively analyzed and validated by X-ray diffraction (XRD) and photoelectron spectroscopy (XPS). The influencing factors of gas sensing properties were studied and the test results of gas sensor were analyzed. The results indicated that the detection using the composite material gas sensors for low concentration NO2 toxic gas could be greatly improved by MWCNTs which were doped on the mixed oxides matrix. A possible mechanism explaining the behaviour of the thin film gas sensor was introduced.

Measurement of Young's Modulus and Poisson's Ratio of Thin Film by Combination of Bulge Test and Nano-Indentation

2008 ◽  
Vol 33-37 ◽  
pp. 969-974 ◽  
Author(s):  
Bong Bu Jung ◽  
Seong Hyun Ko ◽  
Hun Kee Lee ◽  
Hyun Chul Park
Keyword(s):  
Thin Film ◽  
Mechanical Properties ◽  
Young’S Modulus ◽  
Poisson’S Ratio ◽  
Young's Modulus ◽  
Applied Pressure ◽  
Indentation Test ◽  
Poisson's Ratio ◽  
Bulge Test ◽  
Nano Indentation

This paper will discuss two different techniques to measure mechanical properties of thin film, bulge test and nano-indentation test. In the bulge test, uniform pressure applies to one side of thin film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as the elastic modulus and the residual stress. Nano-indentation measurements are accomplished by pushing the indenter tip into a sample and then withdrawing it, recording the force required as a function of position. . In this study, modified King’s model can be used to estimate the mechanical properties of the thin film in order to avoid the effect of substrates. Both techniques can be used to determine Young’s modulus or Poisson’s ratio, but in both cases knowledge of the other variables is needed. However, the mathematical relationship between the modulus and Poisson's ratio is different for the two experimental techniques. Hence, achieving agreement between the techniques means that the modulus and Poisson’s ratio and Young’s modulus of thin films can be determined with no a priori knowledge of either.

A Reexamination of the Extraction of Material Properties Using Nanoindentation

2008 ◽  
Author(s):  
B. Poon ◽  
D. Rittel ◽  
G. Ravichandran
Keyword(s):  
Contact Area ◽  
Material Properties ◽  
Poisson’S Ratio ◽  
Poisson's Ratio ◽  
Nanoindentation Test ◽  
Displacement Curve ◽  
Elastic Solids ◽  
Ratio Effect ◽  
Elastic Plastic ◽  
Tip Radius

The paper reexamines the extraction of material properties using nanoindentation for linearly elastic and elastic-plastic materials. The paper considers indentation performed using a rigid conical indenter, as follows. Linearly elastic solids: The reduction of nanoindentation test data of elastic solids is usually processed using Sneddon’s relation [1], which assumes a linearly elastic infinite half space and an infinitely sharp indenter tip. These assumptions are violated in practical indentation experiments. Since most of the research on the extraction of material properties relies heavily on numerical simulations, we used them to investigate the specimen dimensions required for it to qualify as an infinite body, and the indentation conditions for finite tip radius effect to be negligible. The outcome of this part is firstly, the definition of a “converged” 2D geometry so that additional magnification of the numerical model does not influence the load-displacement curve, and secondly, an explicit relationship between the measured load and displacement that takes into account the finite tip radius. Elastic-plastic solids: Here, the main data reduction technique was proposed by Pharr et al. [2], assuming elastic unloading of a plastic nanoindentation. We investigated the effects of finite tip radius in elastic-plastic indentations and found that the accuracy of the prediction is currently limited by the accurate determination of the projected contact area. This point will be discussed and a new experimental technique to measure the projected contact area will be proposed. The Poisson’s ratio effect in elastic-plastic indentations is found to be different from the linearly elastic case. This leads to the discussion on the applicability of the correction factor (for Poisson’s ratio effect) derived in linear elastic indentations, on elastic-plastic indentations. Finally, a technique to obtain an upper bound estimate of the yield stress for the indented elastic-plastic material (which is an exact estimation for non-hardening materials), will be presented.

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