Round-Robin Tests of Modulus and Strength of Polysilicou

1998 ◽  
Vol 518 ◽  
Author(s):  
W. N. Sharpe ◽  
S. Brown ◽  
G. C. Johnson ◽  
W. Knauss
Keyword(s):  
North Carolina ◽  
Failure Analysis ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Research Society ◽  
Test Methods ◽  
Society Meeting ◽  
A Value ◽  
Production Run ◽  
Materials Research

AbstractThe Young's modulus and strength of polysilicon specimens manufactured in the same production run were measured in four different laboratories. Specimens subjected to in-plane bending were tested at U. C. Berkeley and at Failure Analysis Associates, and tensile measurements were made at Caltech and Johns Hopkins. All specimens were produced at the Microelectronics Center of North Carolina (MCNC).In bending, the Young's modulus for specimens nominally 2 µm thick was measured as 174 GPa and 137 GPa; whereas in tension, a value of 132 GPa was obtained. Modulus values of 136 GPa and 142 GPa were measured in tension on specimens nominally 1.5 µm and 3.5 µm thick. Strengths of the brittle polysilicon were 2.8 and 2.7 GPa in bending and 1.3 GPa for both thicknesses in tension.These preliminary results were presented at Symposium N - Microelectromechanical Structures for Materials Research at the Materials Research Society meeting in April 1998. This paper is a short overview of the test methods — each of which is described elsewhere — and a documentation of the results presented at that time.

The Mechanical Properties of the Cell Surface

1955 ◽  
Vol 32 (4) ◽  
pp. 734-750 ◽  
Author(s):  
J. M. MITCHISON ◽  
M. M. SWANN
Keyword(s):  
Cell Surface ◽  
Young’S Modulus ◽  
Sea Water ◽  
Young's Modulus ◽  
Contractile Ring ◽  
A Value ◽  
Sudden Rise ◽  
Slow Rise ◽  
Stage Yield ◽  
Sperm Aster

1. Measurements with the cell elastimeter on the stiffness of the cell membrane of fertilized sea-urchin eggs show the following general features. There is a sudden rise at fertilization, followed by a fall during the early sperm aster stage to the lowest value reached during development (a Young's modulus of about 0.58 x 104 dynes/cm.2). The stiffness rises slowly until metaphase, after which it rises rapidly to reach a maximum during late anaphase and early cleavage (6.81 x 104 dynes/cm.2). During the later stages of cleavage the stiffness falls again and reaches a value in the second interphase which is about twice as high as in the first interphase. Masurements on naked eggs in calcium-free sea water indicate that the slow rise in metaphase is due to the development of the hyaline layer. 2. Measurements on swollen and shrunken eggs at cleavage indicate that there is no interal pressure in the eggs at this stage, but similar experiments with eggs at the sperm aster stage yield anomalous results. Observations on the wrinkling point in shrunken eggs show that the maximum possible internal pressure is 19 dynes/cm.2 for sperm aster eggs and 500 dynes/cm.2 for cleaving eggs. 3. The bearing of these results on various theories of the mechanism of cleavage is briefly discussed. The rise in Young's modulus of the whole cell surface at cleavage argues against theories depending on the action of the spindle and asters, and against theories proposing a contractile ring in the surface. The rise is, however, what might be expected on the basis of the expanding membrane theory.

scholarly journals Experimental Study of Hardened Young’s Modulus for 3D Printed Mortar

Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7643
Author(s):  
Szymon Skibicki ◽  
Mateusz Techman ◽  
Karol Federowicz ◽  
Norbert Olczyk ◽  
Marcin Hoffmann
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Statistical Correlation ◽  
Test Methods ◽  
Cylindrical Sample ◽  
Experimental Investigations ◽  
Current Standard ◽  
Number Of Layers ◽  
3D Printed

Few studies have focused on determining the Young’s modulus of 3D printed structures. This study presents the results of experimental investigations of Young’s modulus of a 3D printed mortar. Specimens were prepared in four different ways to investigate possible application of different methods for 3D printed structures. Study determines the influence of the number of layers on mechanical properties of printed samples. Results have shown a strong statistical correlation between the number of layers and value of Young’s modulus. The compressive strength and Young’s modulus reduction compared to standard cylindrical sample were up to 43.1% and 19.8%, respectively. Results of the study shed light on the differences between the current standard specimen used for determination of Young’s modulus and the specimen prepared by 3D printing. The community should discuss the problem of standardization of test methods in view of visible differences between different types of specimens.

Polysilicon Tensile Testing With Electrostatic Gripping

1998 ◽  
Vol 518 ◽  
Author(s):  
W. N. Sharpe ◽  
K. Turner ◽  
R. L. Edwards
Keyword(s):  
North Carolina ◽  
Young’S Modulus ◽  
Tensile Testing ◽  
Young's Modulus ◽  
Strain Curve ◽  
Electrostatic Forces ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Force Displacement

AbstractTechniques and procedures are described for tensile testing of polysilicon specimens that are 1.5 or 3.5 νm thick and have various widths and lengths. The specimens are fixed to the wafer at one end and have a large free end that can be gripped by electrostatic forces. This enables easy handling and testing and permits the deposition of 18 specimens on a one-centimeter square portion of a wafer. The displacement of the free end is monitored, which allows one to extract Young's modulus from the force-displacement record. Some of the wider specimens have two gold lines applied so that strain can be measured interferometrically directly on the specimen to record a stress-strain curve.The specimens were produced at the Microelectronics Center of North Carolina (MCNC). When compared with earlier results of wider MCNC specimens that were 3.5 μm thick, the Young's modulus is smaller and the strength is slightly larger.

scholarly journals Material Properties of Wire for the Fabrication of Knotted Fences

2014 ◽  
Vol 2014 ◽  
pp. 1-12
Author(s):  
Dirk J. Pons ◽  
Gareth Bayley ◽  
Christopher Tyree ◽  
Matthew Hunt ◽  
Reuben Laurenson
Keyword(s):  
Tensile Strength ◽  
Young’S Modulus ◽  
Material Properties ◽  
Young's Modulus ◽  
Flexural Modulus ◽  
Test Methods ◽  
Materials Properties ◽  
Three Point Bending ◽  
Insight Into ◽  
Strength And Ductility

This paper describes the materials properties of galvanised fencing wire, as used in the fabrication of knotted wire fences. A range of physical properties are investigated: tensile strength, ductility in tension, Young’s modulus, three-point bending, and bending span. A range of commercially available wire products were tested. The results show that most, but not all, high tensile wire samples met the minimum tensile and ductility requirements. Young’s modulus results failed to provide any meaningful insights into wire quality. Flexural modulus results also failed to provide any insight into wire quality issues, with no statistically significant differences existing between acceptable and problematic wire batches. The implications are that premature fence failures are unlikely to be caused solely by reduced tensile properties. Existing test methods, including tensile strength and ductility, are somewhat incomplete, perhaps even unreliable, as measures of wire quality.

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