Fabrication of high accuracy micro-translation-table for near-field optical data storage actuated by inverted-scratch-drive-actuators

In recent years, development of a next generation high-density recording system has attracted an increasing attention with the improvement of the storage density. One of the attractive technologies to overcome the limit of the storage density is near-field optical data storage. The optical memory with high density and high data transfer rate is highly demanded to utilize an array of nano-scaled light sources for writing and reading bits formed on a recording medium. We have fabricated a micro-translation-table to convey the recording medium to the near-field optical head. The proposed micro-translation-table consists of the inverted scratch drive-actuators (SDAs) which are electrostatically driven. The inverted SDA is powerful and precise due to the stepwise movement. A long distance translation is achieved by repeating the stepwise movement. Fast moving speed, high response and the positioning resolution of the order of 1 nanometer are possible. The inverted SDA has been fabricated with silicon surface micromachining technology. We have proposed a novel mechanism that the SDAs can be retracted to a substrate by applying the voltage between the SDA and a lower electrode. Therefore, the SDAs used for the conveyance are stretched and others are retracted. We have observed that a micro object is translated with the fabricated actuators by applying AC voltage of 600 V at 100 Hz.