We present a novel experimental method for measuring the mechanical properties of nano-thickness materials using a freestanding membrane test. Specially fabricated axisymmetric freestanding membranes are centrally deflected using a spherical indenter attached to a custom-designed MEMS load cell. Experiments on freestanding films allows us to determine directly the mechanical properties of the films, over a broad range of length scales, without the confounding effects of a substrate.

Volume Subject Area:
Microelectromechanical Systems
Topics:
Machinery, Mechanical testing, Microelectromechanical systems, Testing, Mechanical properties, Membranes, Stress
1.
Schiotz
J.
,
Tolla
F. D. D.
, and
Jacobsen
K. W.
, “
Softening of nanocrystalline metals at very small grain sizes
,”
Nature
, vol.
391
, pp.
561
–
563
, February
1998
.
2.
Saif
M. T. A.
,
Zhang
S.
,
Haque
A.
, and
Hsia
K. J.
, “
Effect of native Al2O3 on the elastic response of nanoscale Al films
,”
Acta Materialia
, vol.
50
, pp.
2779
–
2786
, 2002.
3.
Kang
Y.-S.
and
Ho
P. S.
, “
Thickness dependent mechanical behavior of submicron aluminum films
,”
Journal of Electronic Materials
, vol.
26
, no.
7
, pp.
805
–
813
,
1997
.
4.
Oliver
W. C.
and
Pharr
G. M.
, “
An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments
,”
Journal of Materials Research
, vol.
7
, no.
6
, pp.
1564
–
1583
,
1992
.
5.
Haque
M. A.
and
Saif
M. T. A.
, “
Application of MEMS force sensors for in situ mechanical characterization of nanoscale thin films in SEM and TEM
,”
Sensors and Actuators A
, vol.
97–98
, pp.
239
–
245
,
2002
.
6.
Weihs
T. P.
,
Hong
S.
,
Bravman
J. C.
, and
Nix
W. D.
, “
Mechanical deflection of cantilevered microbeams
,”
Journal of Materials Research
, vol.
3
, pp.
931
–
942
, September–October
1988
.
7.
Small
M. K.
and
Nix
W. D.
, “
Analysis of the accuracy of the bulge test in determining the mechanical properties of thin films
,”
Journal of Materials Research
, vol.
7
, pp.
1553
–
1563
,
1990
.
8.
Vlassak
J. J.
, and
Nix
W. D.
, “
A new bulge test technique for the determination of Young’s modulus and Poisson’s ratio of thin films
,”
Journal of Materials Research
, vol.
7
, pp.
3242
–
3249
,
1992
.
9.
F. Larmer and A. Schilp, “Method for anisotropically etching silicon,” Patents DE4241045, US 5501893, and EP 625285, 1992.
10.
Zhang
Z. L.
and
McDonald
N. C.
, “
Fabrication of submicron high-aspect-ratio GaAs actuators
,”
Journal of Microelectromechanical Structures
, vol.
2
, pp.
66
–
73
, June
1993
.
11.
Shaw
K. A.
,
Zhang
Z. L.
, and
McDonald
N. C.
, “
SCREAM I: a single mask, single-crystal silicon, reactive ion etching process for microelectromechanical structures
,”
Sensors and Actuators A
, vol.
40
, pp.
63
–
70
,
1994
.
12.
Begley
M. R.
and
Mackin
T. J.
, “
Spherical indentation of freestanding circular thin films in the membrane regime
,”
The Journal of Mechanics and Physics of Solids
, v
52
, n
9
, September,
2004
, p.
2005
–
2023
13.
Tabata
O.
,
Asahi
R.
,
Funabashi
H.
,
Shimaoka
K.
, and
Sugiyama
S.
, “
Anistropic etching of silicon in TMAH solutions
,”
Sensors and Actuators A
, vol.
34
, pp.
51
–
57
,
1992
.
14.
R. Frisch-Fay, Flexible Bars. Butterworths, 1962.
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