AFM characterization of nanopositioner in-plane stiffnesses (original) (raw)
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Proceedings of …, 2002
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Calibration aspects of a measurement system for an ultra-stiff nanopositioning system
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A Large Range XY flexure stage for nanopositioning
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2014 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, 2014
A flexure-guided serial-kinematic XYZ nanopositioner for high-speed Atomic Force Microscopy (AFM) is presented in this paper. Two aspects influencing the performance of serial-kinematic nanopositioners are studied in this work. First, mass reduction by use of tapered flexures is used to enhance the natural frequency of the nanopositioner. Second, a study of possible sensor positioning in a serial-kinematic nanopositioner is presented. An arrangement of sensors for exact estimation of cross-coupling is incorporated in the proposed design. Characterization in terms of range, hysteresis, cross-coupling and dynamic response of the nanopositioner is presented. Scanning results up to 640 Hz are also furnished. Outcomes and future work are discussed in conclusion.
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Sensors and Actuators A: …, 2005
The objective of this paper is to demonstrate the application of the microscopic hole method as an alternative approach to assess the elastic properties of polycrystalline silicon freestanding thin films employed in microelectromechanical system (MEMS) devices. This method relies on the inverse solution of the problem of a hole in a plate. When accurate and repeatable full-field nanometric displacements are acquired in the vicinity of circular, micron-sized perforations, the elastic modulus and Poisson's ratio computed via this method agree well with those obtained from uniform tension experiments. In this work, the nanoscale displacements were obtained through a digital image correlation (DIC) analysis of atomic force microscopy (AFM) images acquired at various applied loads. The accuracy in determining both elastic constants hinges upon the selection of the optimum location at the hole perimeter for the acquisition of local displacements. Using a numerical analysis, the area of maximum compression was determined to provide the most accurate determination of Young's modulus (E = 155 ± 6.6 GPa) and Poisson's ratio (ν = 0.20 ± 0.04) which agreed very well with measurements obtained from uniform tension tests. The advantage of this hole method, an inverse problem approach, is that both isotropic elastic constants can be recovered from very small material domains (10 m × 10 m or smaller) with knowledge of the displacement field in only one direction.
Design and performance of a test rig for evaluation of nanopositioning stages
Measurement Science and Technology, 2019
Nanopositioning stages are used in many areas of nanotechnology and advanced materials analysis, often being integrated into analytical devices such as scanning probe and optical microscopes and manufacturing devices (e.g. lithographic systems). We present a metrological instrument, together with software, designed for traceable evaluation of stage performance. The system capabilities and performance are illustrated by measurement of stages of different levels of accuracy, including a low cost custom built stage manufactured by 3D printing. The traceability of the system is described and main uncertainty sources are discussed. Guidelines are given for the specification of stage performance.