Nanopositioning for storage applications

In nanotechnology applications, nanopositioning, i.e., nanometer-scale precision control at dimensions of less than 100 nm, plays a central role. One can view nanopositioners as precision mechatronics systems aiming at moving objects over a certain distance with a resolution that could be as low as a fraction of an Ångström. Actuation, position sensing and feedback control are the key components of nanopositioners that determine how successfully the stringent requirements on resolution, accuracy, stability, and bandwidth are achieved. Historically, nanopositioning has played a critical role in scanning probe microscopy (SPM), and it appears that it will play a crucial role in emerging applications such as lithography tools and semiconductor inspection systems, as well as in molecular biology, nanofabrication, and nanomanufacturing. Moreover, it is becoming an important requirement in storage systems, ranging from novel probe-based storage devices to mechatronic tape-drive systems, to support the high areal density or storage capacity needs. This paper will review control-related research in nanopositioning for two extreme cases of data-storage systems, namely, in probe and in tape storage.