Scanning Probe Microscopy, Micromechanics, and Storage

Interaction and actuation mechanisms used in scanning probe microscopies (SPM) have inherent potential for storage applications, but many unresolved conceptual and technical questions have precluded the serious assessment of this potential so far. The intrinsic properties of SPM instrumentation and tip/sample interactions allow, however, a number of important parameters and their ultimate values to be predicted. Some implications and conceptual approaches resulting from a comparison of these properties with the performance of modern storage devices will be discussed in the present paper. In order to cope with and surpass established technologies, massive parallelism of SPM-type recording heads will be necessary, a condition that might be satisfied in an elegant manner by using SPM-type circulated piezoelectric flexural actuators instead of the common rotating disk devise. Operation of an entire array of recording heads will require highly precise micromechanical manufacturing and/or sophisticated control mechanisms. For the sake of simplicity and in order to achieve high data rates, it is proposed that future research efforts be concentrated on ``long-range'' and ``fast'' SPM interactions. Near-field optics (exploited in scanning near-field optical microscopy) having a potential bit size of 30-100 nm (50500 Gbit/inch2) and access times several orders of magnitude faster than those of rotating disk devices. might fulfill these requirements to a large extent, and the simplest implementation could be a read-only, CD-ROM-type storage device