| LIGA technology is a new perfect means for micro fabrication, which is developed in recent years. LIGA technology mainly includes X-ray lithography, electroforming and plastic molding. Because synchronous X-ray has very perfect parallel quality, strong radiation intensity and continuous spectrum, 1000 μm deep microstructure which aspect ratio is 500 can be fabricated by LIGA technology. LIGA technology has its particular merits in fabricating deep microstructure and very important status in high aspect ratio microstructure fabrication. For the LIGA technology appearance, many microstructures, which could not be achieved, now can be made out. But its expensive X-rays photolithograph equipments and complex marks fabrication process limited its wide application. So, it will promote MEMS research if we can fabricate high-aspect microstructures by combining common uv-photolithograph technology and other MEMS techniques . In the article, a new quisa-LIGA technology based on LIGA is discussed by giving an example of the fabrication of a drivable micro gear. This technology have three features: above all, it uses ultraviolet radiation in photolithograph whose equipment is cheap; secondly, plate pattern is made up using three-layers photoresist technology, so that the thickness of the micro gear can be over 40 μm and the aspect ratio is 2; finally, metal sacrificial layer technology is used to control the clearance between the micro gear's hole and shaft which is get by plating copper. From the study, a lot of detailed quasi-LIGA process parameters have been gained, and a suit of integrate quasi-LIGA process has been proposed, which will be great significance to the fabrication of the micro electromagnetism relay which is one of the tasks of national "863 program "and other MEMS products.
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