Dual-cup coating apparatus

摘要

A liquid coating apparatus that is adapted for dispensing two or more different liquids and a method for using such apparatus are disclosed. In the apparatus, when two different liquids are dispensed in the same coating apparatus, two separate drain cups are utilized in which an upper drain cup is constructed in a toroidal shape and formed in two symmetrical halves such that they may be withdrawn from an operating position outwardly to allow a wafer platform and a liquid spray nozzle to be lowered into a lower drain cup for dispensing a second liquid material. The lower drain cup can be mounted concentrically with the upper drain cup. The present invention novel apparatus allows at least two different liquids to be processed in the same coating apparatus such that chemical reactions between the different liquids and the resulting particle formation and contamination problems can be avoided.