Patent ID: 6059880
Filing Date: 2000-05-09
Classification: G03F,Y10T

Abstract:
A coating apparatus configured to coat a substrate with a treatment solution, comprising:a substrate holding member configured to hold the substrate;a treatment solution supply having a plurality of treatment solution tanks which contain treatment solutions of different compositions;a solvent supply which contains a solvent;a confluence valve coupled to the solvent supply and the treatment solution supply, said confluence valve including:a main treatment solution passage,switch means for selectively switching a transfer of a treatment solution from said plurality of treatment solution tanks to said main treatment solution passage,a solvent passage coupled to the solvent tank,a valve seat provided in the solvent passage,a first valve body for opening and closing the solvent passage, anda first valve cylinder for bringing the first valve body into and out of contact with the valve seat;first pump means for supplying the treatment solution from the treatment solution supply to the confluence valve, said first pump means including a first flexible tube coupled to a treatment solution reservoir, and a first pump cylinder means for reciprocating the flexible tube;second pump means for supplying the solvent from the solvent supply to the confluence valve, the second pump means including a second flexible tube coupled to a solvent reservoir, and a second pump cylinder means for reciprocating the flexible tube;a mixer provided downstream of the confluence valve and configured to mix the treatment solution and the solvent supplied from the confluence valve;nozzle means coupled to said mixer and having a solution discharge portion for applying a solution from the mixer, to the substrate held by the substrate holding member;a discharge valve located downstream of the mixer and in the vicinity of the nozzle means and configured to permit and interrupt a flow of a solution from the mixer to the nozzle means;a sensor means for sensing an amount of displacement of said flexible tubes; andcontrol means for controlling said first and second cylinder means on the basis of a detection signal from said sensor means thereby controlling the first and second pump means to adjust a mixture ratio of the treatment solution to be supplied from the treatment solution supply to the confluence valve, to the solvent supplied from the solvent supply to the confluence valve.