The nanomechanical characterization of an individual nanostructure involves complexities related to their positioning, alignment and attachment to probes. Several ingenious experimental techniques have been proposed and implemented in the recent past to understand the nanomechanical behavior of individual nanostructures [1],[2]. This paper reports the development of a novel nanomechanical characterization device that enables independent measurements of both load and displacement history with microNewton force and nanometer displacement resolution. Moreover, the device is well suited for in-situ testing with inside a SEM/FIB, that allows continuous high resolution imaging during nanomechanical straining. The device (Fig. 1a) comprises of two main parts: (a) a commercially available three-plate capacitive transducer (Hysitron, Inc) that serves both as an actuator and a force sensor; and (b) a nanomanipulator (Kliendiek MM3A) that facilitates transportation and positioning of the nanoscale structures with nanoprecision. Electrospun polyaniline fibers, ～1μm diameter were utilized for nanomechanical characterization. An individual polyaniline microfiber was isolated from a non-woven sheet of electrospun polyaniline microfibers by employing the Kleindiek nanomanipulator with in a dual beam FIB/SEM. One end of the sample was then micro-welded to the nanomanipulator Pt/Ir probe tip by depositing platinum using the EBID/IBID process in conjuction with a micro-delivery gas injection system that can create a local platinum rich precursor gas environment. The microfiber specimen was then either pulled from the substrate or cut to the desired length using the ion beam. The other end thus obtained was then transported to the actuator probe tip stationed on the force transducer, aligned parallel to the loading axis and then spot welded onto the actuator probe tip using the IBID process (Fig. 1,b).
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