Chapter 3 - Manufacturing of AM LCDs

Abstract

This chapter is designed to enlist and elaborate the steps in the basic manufacturing process of active matrix liquid crystal display (AMLCD) panels. Panel manufacturing is usually subdivided in thin film transistors (TFT) array manufacturing, liquid crystal (LC) assembly, and module assembly. TFT array production shows some similarities with semiconductor manufacturing. Many of the methods, types of equipment, and expertise acquired in the semiconductor industry have been successfully applied to AMLCD array processing. They include yield optimization techniques and clean room and facility operation, and are applied to the color filter plate manufacturing as well. Amorphous and polycrystalline silicon thin films turn out to be quite suitable for AMLCDs and are easily patternable using etch chemistry derived from silicon processing in the semiconductor industry. The front end of AMLCD manufacturing is highly automated with expensive equipment and is therefore very capital-intensive. Back-end processing that includes module assembly and assembly of the final product is more labor-intensive and has often been moved to low-labor-cost regions in Asia. Most LCD panel manufacturers do not reveal their manufacturing yield, for competitive reasons. Yield improvements have been striking due to the introduction of automation and by improvement of processes, materials, and component quality.