Improvement in contamination control for a LCD color filter coater was studied by using a mini-environment design. Different operating conditions of the door and the exhaust of the mini-environment were studied. Measurements of particle concentration, flow field, and VOC concentration were performed. Both the particle contamination to the coating process and

the VOC contamination to the outside cleanroom environment were considered in this study. It was found that a mini- environment could be designed to significantly reduce the particle concentration. Also, the exhaust of the mini-environment was found to affect the flow field in the mini-environment and result in an increase of particle contamination at a level close to the coating process. The design of the mini-environment requires optimal operating conditions.