Nanotechnology is the science of understanding matter and the control of matter at dimensions of 100 nm or less. Encompassing nanoscale science, engineering, and technology, nanotechnology involves imaging, measuring, modeling, and manipulation of matter at this level of precision. An important aspect of research in nanotechnology involves precision control and manipulation of devices and materials at a nanoscale, i.e., nanopositioning. Nanopositioners are precision mechatronic systems designed to move objects over a small range with a resolution down to a fraction of an atomic diameter. The desired attributes of a nanopositioner are extremely high resolution, accuracy, stability, and fast response. The key to successful nanopositioning is accurate position sensing and feedback control of the motion. This paper presents an overview of nanopositioning technologies and devices emphasizing the key role of advanced control techniques in improving precision, accuracy, and speed of operation of these systems.

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Control can enable high-bandwidth nanopositioning needed to increase the operating speed of scanning probe microscopes (SPMs). High-speed SPMs can substantially impact the throughput of a wide range of emerging nanosciences and nanotechnologies. In particular, inversion-based control can find the feedforward input needed to account for the positioning dynamics and, thus, achieve the required precision and bandwidth. This article reviews inversion-based feedforward approaches used for high-speed SPMs such as optimal inversion that accounts for model uncertainty and inversion-based iterative control for repetitive applications. The article establishes connections to other existing methods such as zero-phase-error-tracking feedforward and robust feedforward. Additionally, the article reviews the use of feedforward in emerging applications such as SPM-based nanoscale combinatorial-science studies, image-based control for subnanometer-scale studies, and imaging of large soft biosamples with SPMs.

This article studies ultra-high-precision positioning with piezoactuators and illustrates the results with an example Scanning Probe Microscopy (SPM) application. Loss of positioning precision in piezoactuators occurs (1) due to hysteresis during long range applications, (2) due to creep effects when positioning is needed over extended periods of time, and (3) due to induced vibrations during high-speed positioning. This loss in precision restricts the use of piezoactuators in high-speed positioning applications like SPM-based nanofabrication, and ultra-high-precision optical systems. An integrated inversion-based approach is presented in this article to compensate for all three adverse affects—creep, hysteresis, and vibrations. The method is applied to an Atomic Force Microscope (AFM) and experimental results are presented that demonstrate substantial improvements in positioning precision and operating speed.