A novel laser micro/nano-machining system for FPD process

Laser machining technology has potential to be adopted as micro- and nano-fabrication equipments in the field of flat panel display (FPD) industry. The equipments repair short, open or protrusion defects by cutting and welding using high-power laser. The equipments should be able to carry large sized mother glass and have high productivity and accuracy. To meet the requirements, the equipment should travel long range with higher speed and higher precision than the conventional. In this paper, a high precision decoupled dual-stage is proposed to transfer and position FPD mother glass. The dual-stage system consists of coarse stage actuated by linear motor and fine stage by moving magnet type voice coil motor. The control and design of the two stages are required to be considered independently if possible in order to take advantage of modular approach. In order to suppress disturbance from the coarse to fine stage, they are designed without mechanical connections. Dual-servo tracking controller is applied by adding fine controller to conventional coarse controller. Reaction force between fine and coarse stages is compensated by a force compensator (FC) because it is detrimental to positioning and scanning. By simulation and experiment, the performance of dual-stage is evaluated and compared.