Automated equipment considerations for liquid crystal display production

Abstract

The recent development of large multiplex and active matrix liquid crystal displays (LCD's) has increased the need for efficient automation. Spacing and plate-to-plate alignment control both have to be improved and cost effective production of these high information content systems requires efficient processing and high yields. Yield is dependent on process and contamination control and can only be effectively improved by process development and automation. While automation is necessary, a key problem is designing the production facility to be cost effective. This has been achieved in the past by producing large quantities of the same product in order to avoid costs associated with changing machine set-ups. The array process for standard LCD's was developed to minimise handling costs and to minimise investment by designing the production line to work with one substrate size. This system allows production of different sizes and styles of product within the line substrate size limitation, the major constraint being efficiency of fit. Substrate handling problems and tighter process control requirements now require the development of standardised systems to cope with the large substrate sizes. The design of automated LCD production equipment is discussed in relation to the problems of automating in a cost effective manner.