A MEMS Platform for Mechanical Testing of Soft Nanofibers and Nanowires

1. Abstract In this report, design, operation principles and finite elements analysis of a novel MEMS based mechanical testing platform for highly deformable nanofibers and nanowires is presented. Mechanical actuation is accomplished through a group of five thermal actuators by sequencing electrical inputs to a coordinated grip-release and pulling mechanism. This new actuation device is capable of generating tens of micronewtons force and total displacement of 100 μm. Unlike most surface micromachined MEMS actuators, such as nanotractors and scratch drives, the proposed platform is designed so that the force generated by the actuator does not decay with increasing travel length. Maintaining the applied force over large travel lengths is accomplished by separating the actuating and moving parts of the device. A leaf spring folded beam loadcell is implemented to measure the force on the sample. Primarily, this MEMS device is designed for mechanical characterization of electrospun polymer nanofibers.