Semiconductor manufacturing systems and ultra-precise machine tools now require nanometer-scale positioning accuracy. To improve positioning accuracy, it is efficient to support the top table with a noncontact guide system to prevent guide friction and heat transfer from the lower table or base. A magnetic levitation (maglev) stage can accomplish ultra-precise positioning accuracy with six-degrees-of-freedom (6DOF) control even in vacuum conditions. However, if the gravity of the levitated table is supported by the thrust of a linear motor, heat generation from the motor coil dramatically increases. In addition, a larger motor is required, which causes the moving mass to increase and the mechanical response to deteriorate. We aimed to develop a compact maglev stage for which the levitated mass is less than 1 kg and that is dramatically more lightweight than existing maglev stages. This compact feature was enabled by our newly proposed gravity compensation system with repellent force and a planar motor structure. The developed stage system also has long strokes, specifically 200 mm in the X and Y-directions on a horizontal plane. We designed a maglev stage with the following design concepts to create its compact structure: (1) Reduce top-table mass to minimize the motor dimensions and enable a light weight and high responsiveness. (2) Measure the top-table position from the base to eliminate positioning error and isolate vibrations of the coarse stage. (3) Install a motor in a symmetrical layout in view from the Z-axis to enable the same driving characteristics between the X and Y axes. The results of the performance evaluation showed that the developed maglev stage system with a compact structure with 0.81 kg levitated mass has ±10 nm positioning stability.

半导体制造系统和超精密机床现在需要纳米级的定位精度。为了提高定位精度，有效的是用非接触式导向系统支撑顶桌，以防止导向摩擦和热量从下桌或基座传递。磁悬浮（maglev）平台即使在真空条件下也可以通过六自由度（6DOF）控制实现超高精度的定位精度。但是，如果悬浮工作台的重力由线性电动机的推力支撑，则电动机线圈产生的热量会大大增加。另外，需要更大的电动机，这导致运动质量增加并且机械响应变差。我们旨在开发一种紧凑的磁悬浮平台，其悬浮质量小于1 kg，并且比现有的磁悬浮平台轻得多。这种紧凑的功能是由我们新近提出的具有推斥力和平面电动机结构的重力补偿系统实现的。发达的舞台系统还具有较长的行程，特别是在水平面的X和Y方向上具有200 mm的行程。我们设计了具有以下设计概念的磁悬浮平台，以使其结构紧凑：（1）减少桌面质量，以最大程度地减小电机尺寸并实现轻量化和高响应性。（2）从底座测量顶盘位置，以消除定位误差并隔离粗台的振动。（3）从Z轴的角度对称地安装电动机，以在X轴和Y轴之间实现相同的驱动特性。性能评估结果表明，开发的磁悬浮载物台系统结构紧凑，悬浮质量为0.81 kg，具有±10 nm的定位稳定性。