A compact XYZ scanner for fast atomic force microscopy in constant force contact mode

The design and characterization of a fast flexure-based, parallel-kinematics XYZ scanner for atomic force microscopy is presented in this article. The objective of the project is to design a AFM scanner with the ability to scan an image at high-speed and high resolution. Finite-element analysis was used to optimize the scanner´s design in order to achieve high resonance frequencies. Experimental results show that the scanner has resonance frequencies of 10kHz at the X, Y and Z axes. To evaluate the performance of the scanner, it was installed into a NT-MDT microscope to obtain images. A 3.5μm×3.5μm image of a calibration grating was successfully recorded up to a scan speed of 625Hz in open-loop. Simulations show that the scanner can be operated up to 1025Hz with no oscillations observed in the fast axis. The scan rate can be further increased by means of feedback or feedforward control. The device outperforms commercial AFM scanners that typically work at scan frequencies below 20-30Hz.