SYSTEM FOR CONTROLLING DENSITY OF CHEMICALS

PURPOSE: A system for controlling a density of chemicals is provided to improve yield and productivity by increasing precision of a process, and to reduce delay time of the process as compared with a conventional method of artificially measuring the density of the chemicals to adjust the density. CONSTITUTION: A pipe-type flow cell(40) made of a light transparent material is installed on a chemical circulation line(24) formed in a chemical bath(20). A density detecting sensor(50) detects a density of wet chemicals(22) flowing in the flow cell as an electrical signal by using light of a specific wavelength for detecting the density of the chemicals. A controller(60) calculates the density of the chemicals by comparing a signal outputted from the density detecting sensor with density data of previously-stored reference chemicals, and outputs a signal for controlling the density of the chemicals by an established density. Respective solenoid valves control a quantity of high density chemicals and deionized water induced into the chemical bath, and opens/shuts according to an output signal of the controller.