Ultraprecision Micro Machining of Structures with High Aspect Ratio.

In recent years, the ultraprecision micro machining technology is greatly expected in a variety of fields such as optical instruments, electronic devices, medical equipments, etc. At the time, it is essential to meet the requirement of producing various shapes, one of which is a structure with a high aspect ratio. Such a structure is applicable, for example, to a shaft of micro robot, a long part of micro actuator and micro machine, a micro needle for syringe, etc. However, it is extremely difficult to fabricate the structure with a high aspect ratio since it is easily crooked and broken during cutting. Thus, it is at first intedned to produce prismatic micro tower with a high aspect ratio, which has never been fabricated until now, by applying the ultraprecision milling technology with a single crystal diamond cutting tool. This method enables to accurately create a variety of micro structures with a high aspect ratio. In addition, the study also proposes a new machining method to create micro pin array, avoiding the contact of cutting edge with already machined parts again. Micro pin array may be applied to painless micro needles for syringe. As a result, it is found that the proposed method has the potential of producing a variety of micro structures with a high aspect ratio.