Monolithic integration of nanoscale tensile specimens and MEMS structures

Abstract

Nanoscale materials often have stochastic material properties due to a random distribution of material defects and an insufficient number of defects to ensure a consistent average mechanical response. Current methods to measure the mechanical properties employ MEMS-based actuators. The nanoscale specimens are typically mounted manually onto the load platform, so the boundary conditions have random variations, complicating the experimental measurement of the intrinsic stochasticity of the material properties. Here we show methods for monolithic integration of a nanoscale specimen co-fabricated with the loading platform. The nanoscale specimen is gold with dimensions of ∼40 nm thickness, 350 ± 50 nm width, and 7 μm length and the loading platform is an interdigitated electrode electrostatic actuator. The experiment is performed in a scanning electron microscope and digital image correlation is employed to measure displacements to determine stress and strain. The ultimate tensile strength of the nanocrystalline nanoscale specimen approaches 1 GPa, consistent with measurements made by other nanometer scale sample characterization methods on other material samples at the nanometer scale, as well as gold samples at the nanometer scale. The batch-compatible microfabrication method can be used to create nominally identical nanoscale specimens and boundary conditions for a broad range of materials.

Mechanics of Crystalline Nanowires: An Experimental Perspective

“…Figure 7(a) shows the MEMS stage with the thermal actuator and the capacitive load sensor. A number of similar MEMS stages have been developed thereafter for testing a wide variety of 1D nanostructures [125][126][127][128][129][130][131][132].…”

Improvement of thin film tensile testing technology using process integrated specimen and considering its out-of-plane deformation

“…The specimen elongation is thus determined from the deflection profile. On the other hand, the existing approaches determine the specimen elongation by considering its in-plane deformation only [6][7][8][9]. In comparison, the study exhibits a more accurate method to determine specimen elongation.…”

“…In general, the material properties of thin films are different with those determined from the bulk counterparts. Thus, the material properties characterization of thin films such as elastic modulus, residual stress, and fracture stress has attracted lots of attentions [1][2][3][4][5][6][7][8][9].…”

“…Various approaches have been reported to extract the precise results, such as off-chip tensile testing [2][3][4][5], and on-chip tensile testing [6][7][8][9]. The off-chip tensile testing is similar with conventional tensile testing for bulk material.…”

Young's Modulus Measurement of Submicron-thick Aluminum Films Using Fan-shaped Silicon Resonators

“…(2) Knowledge of the mechanical properties of submicron-thick films is indispensable for the structural design of devices with such thin films. To experimentally measure the mechanical characteristics at the nano-or submicron scale, tensile, (3)(4)(5)(6)(7)(8)(9)(10)(11) bulge, (12,13) ultrasonic, (14)(15)(16) and nanoindentation (17,18) tests are typically performed. Among these tests, the tensile test is representative even for nanomaterials, although is well known as a commonly used method for bulk materials.…”