Integrated tracking and focusing micro lens actuators based on silicon bulk micromachining

We demonstrate here the fabrication of integrated tracking (horizontal) and focusing (vertical) micro lens actuators which are implemented on silicon-on-insulator (SOI) wafer using silicon bulk micromachining. The micro actuators that consist of flexures, a lens holder and comb structures with electrodes can realize two-dimensional movements of one objective lens for optical storage applications. DC and frequency responses of the integrated tracking and focusing actuators with or without lens are experimentally demonstrated by applying voltage to the micro lens actuators. The displacements of the proposed actuators have good linearity versus the square of the voltages in tracking and focusing directions. These experimental results show good agreement with theoretical predictions.