Precise positioning of a micro conveyor based on superconducting magnetic levitation

The design and the driving characteristics of a micro conveyor based on superconducting magnetic levitation are reported. This actuator consists of three parts; a superconductor (Y-Ba-Cu-O), a stator layer made by patterned copper electrodes (line pitch: 180 μm, width: 70 μm) on the polyimide film and a slider with four permanent magnets (the size of one magnet is 1 mm cube). This conveyance actuator is free from particle generation, because there is no friction by the magnetic levitation. The position of the slider is controlled by the current in the patterned electrodes. We have obtained quick conveyance (280 μm/s over 2.8 mm) and precise positioning with an accuracy of 40 μm by combining the step actuation in the entire area and the micro-step actuation in the local area near the target position