Contamination Control Strategy based on Particle Flow Behavior near Fast Moving Devices in Flat Panel Display Fabrication Cleanroom

In flat panel display (FPD) fields, the defect rate of the final products yields the rate of particle deposition on FPD panels. Every best endeavor has been made to maintain a clean fabrication environment. However, contamination by airborne particles is still significant. Moreover, contamination by particles near fast moving devices such as a lift or loader has been reported as being serious. Existing well-known treatments for contamination control never worked near fast moving devices. Thus, at this stage, devising a new contamination control strategy based on the analysis of particle flow behavior upon device movement is inevitable to increase FPD productivity. In this study, the particle flow behavior near a fast moving lift is analyzed based upon the results of two and three dimensional transient flow simulations. The simulation results show consistency, insisting that the proposed approach is proper and reliable. Based on our experience associated with FPD cleanrooms and equipment, a new contamination control strategy for the moving lift system in a FPD cleanroom is proposed

1. Introduction

In the Flat Panel Display (FPD) fabrication field for Liquid Crystal Display (LCD), Plasma Display Panel (PDP), Electro Luminescent Display (ELD), and Field Emission Display (FED) manufacturing [1], the defect rate of final products is significantly affected by airborne contamination, and it is becoming increasingly significant along with the growth of the FPD market.