Measurement of mechanical properties for dense and porous polymer films having a low dielectric constant

Abstract

Governing factors in stress response of nanoparticle films on water surface J. Appl. Phys. 110, 102218 (2011) Nanomechanical properties of sputter-deposited HfO2 and HfxSi1-xO2 thin films J. Appl. Phys. 110, 043527 (2011) Effect of epitaxial strain on the cation distribution in spinel ferrites CoFe2O4 and NiFe2O4: A density functional theory study Appl. Phys. Lett. 99, 081916 (2011) Direct measurement of intrinsic critical strain and internal strain in barrier films J. Appl. Phys. 110, 044907 (2011) Misfit dislocation formation via pre-existing threading dislocation glide in (112) We measured the mechanical properties of dense and porous polymeric films, the modified polyarylethers, which have a low dielectric constant varying from 2.7 to 1.8, by combining three different methods; membrane bulge test, nanoindentation, and single-substrate bending beam method. The elastic modulus and initial stress measured from these three methods are in good agreement. The substrate effect was observed in the measurements by nanoindentation. Data obtained by nanoindentation show a significant dependence on the film thickness and the displacement depth of the indenter. However, the hardness of the low dielectric constant thin film does not depend on thickness and only slightly depends on the indentation depth. A tentative analysis is proposed to explain the results.

Determining the mechanical properties of human corneal basement membranes with atomic force microscopy

“…A second explanation for the observed modulus increase may be the reversible compression of the porous membrane under the AFM tip during indentation. Compression of the basement membrane would result in a higher density of membrane fibers and “crosslinks”, which may in turn cause an increase in the modulus (Xu et al, 2000). Similarly, a local, permanent, change in the membrane structure may occur upon indentation (strain hardening), creating an increased membrane density and subsequent increase in elastic modulus.…”

Deformable and conformal silk hydrogel inverse opal

“…minimum UV-exposure time required for the stable SHIO was 2 h. The elastic modulus of the silk hydrogel film was increased (more rigid), along with the reduced elastic deformation range, when the UV-exposure time increased. And, we observed that the elastic modulus of the SHIO was smaller than that of the bulk silk hydrogel film due to porosity of the SHIO (more elastic) (27). The elastic deformation range of the SHIO was 10%, similar to bulk, and the optical response was significantly weakened at strains greater than the elastic range (Fig.…”

Synthesis and characterization of porous polymeric low dielectric constant films

“…23,24 The elastic modulus and initial stress measured from these three methods are in good agreement. 25 For the dense film samples, a Young's modulus of 3.9 GPa was obtained independently from both the bulge test and nanoindentation methods. The initial stress of 35 MPa and 16 MPa for the dense and porous film samples, respectively, was also obtained from both the bulge test and single-substrate bending beam methods.…”