Development of Micromachining Tool Driven by Radiation Pressure

点击翻译按钮获取中文摘要

Optical trapping technology, which utilizes radiation pressure to control and manipulate microscopic particles, has been widely used in various fields, such as biology and microchemistry. In this study, we propose that optical trapping technology can also be used in micromachining. Some designed-shaped-particles made of diamond, which can not only be trapped by the trapping force but also rotated by the optical torque, might be used as tools for micro-grinding or polishing. The designed-shaped-particle is used as a micromachining tool driven and controlled by radiation pressure. A simulator has been developed based on our mathematical model and the motion of arbitrary shaped particles exerted primarily by trapping force and optical torque can be defined. A micromachining tool is designed based on simulation results and fabricated by using photolithography techniques. Main results of this study are summarized as follows(1) A designed-tool composed of a fin part and a tool part is propos … More ed. The fin part is geometrically designed for the control of radiation pressure and efficient rotation. The tool part made of diamond has a sharp edge for micromachining.(2) A diamond abrasive grain with arbitrary shape is optically trapped and driven on a silicon wafer surface. The experimental results show that the trapped abrasive grain can be used for micromachining with nanometer order resolution.(3) We confirmed controllable rotation of a silica particle and a diamond abrasive grain trapped using a focused laser beam with circular polarization experimentally. Rotation rate is changeable by changing polarization state.(4) The movement behavior of a designed-tool made of silica trapped in air has been predicted and it has been shown that high rotation speed of 3800 rpm can be achieved when the torque produced by the laser beam is balanced by the drag torque exerted by the surrounding air. This gives a good verification that designed-tool made of silica or diamond trapped by laser beam can be used in nanometer machining.(5) The fabrication process for a designed-tool made of diamond is established based on the photolithograph technique and the diamond thin film deposition. Two sizes of the prototyping are fabricated and evaluated their tolerances and functions. Less