Wet Etching Processes and Equipment

Summary

Wet etching is characterized by lower running costs than dry etching. The principal characteristic of wet etching is that it is isotropic etching, which means that it is unsuitable for microfabrication. The increasing size of the mother glass is one factor that has brought about an increase in the running costs of wet etching. In addition to the increased volume of etchant, the increase of deionized (DI) water that is used for rinsing after etching has also become a problem due to the mother glass becomes larger. This chapter covers the current applications for wet etching, as well as the issues currently faced by this technology and the ways of resolving them. In the liquid‐crystal display (LCD) manufacturing process, wet etching is still used in the process for gate electrodes, via holes, source and drain (S/D) wiring, and pixel electrodes. Other advantages of wet etching include the long equipment maintenance cycle and simple maintenance tasks.