掩模移动曝光系统精密定位工件台研制

Development of Precision Positioning Workpiece Stage in Mask Moving Exposure System

为满足掩模移动曝光技术制作微光学元件的要求,研制了接近式曝光系统中使用的x-y二维精密移动工件台。该工件台由x-y二维整体手动工作台子系统、x-y二维掩模精密移动台子系统和承片台子系统组成。利用一个方导轨和两对V形导轨组成的滚动导轨副实现了x向和y向精密移动的导向功能;利用驱动器、电机、光栅、细分卡、单片机构成的闭环控制系统保证了x和y向的运动精度;在气浮的作用下,利用掩模版靠平基片实现了调平功能;利用差动螺旋机构和1∶2杠杆缩小机构实现了间隙的调整功能。经检测,工件台在8 mm的工作行程范围内,沿x,y方向移动的直线性分别达到了4″和3″,两个方向的正交性达到了10″,运动定位精度达到了1.2μm。

A x-y 2 dimension precision motion stage used in proximity exposure system was developed to meet the demand of manufacturing micro-optical elements by mask moving exposure technique. The stage is composed of three subsystems which are a x-y 2 dimension manual integral stage, a x-y 2 dimension mask precision motion stage and a wafer stage. The guide function of the precise motion on the x-and y-directions was finished by a rolling guide pair made of a direction guiding orbit and two V-type of guiding orbits. The precise motion positions on both the x-and y-directions was carried out by a close-loop control system which was composed of step motor, actuator, raster sensor, subdivision circuit and SCM. Under the supporting of the pneumatic, the horizontal adjustive function of the substrate was carried out by closing the mark to the substrate and the adjusting of the gap between substrate and mask was carried out by the differential screw structure and the 1:2 level structure. Within a 8 mm traveling path, the measured results show that linear degrees on the x-and y-directions are respectively 4 double prime and 3 double prime and the verticality between x-and y-directions is 10 double prime and the motion positioning accuracy is 1.2 μm.