Etching solution concentration measurement device and etching solution concentration measurement method

Abstract

The invention relates to an etching solution concentration measurement device and an etching solution concentration measurement method. The measurement device comprises a concentration measurement mechanism and an acid mist removing mechanism connected with the concentration measurement mechanism, wherein the acid mist removing mechanism is used for removing acid mist inside the concentration measurement mechanism, the concentration measurement mechanism is used for receiving etching solution in real time, measuring absorbance of all acids of mixed acid of the etching solution in a no-acid-mist environment, and calculating the concentrations of all acids in the mixed acid of the etching solution according to the absorbance. The concentration measurement device overcomes the interference of the acid mist to the measurement of acid concentration of the mixed acid of the etching solution, so as to rapidly and accurately determine the concentrations of all acids of the mixed acid of the etching solution in an online manner; drying gas can be used circularly and the purpose of saving resources is achieved.

Description

technical field [0001] The invention relates to the technical field of etching liquid, and more specifically, relates to an etching liquid concentration measuring device and method. Background technique [0002] Wet etching is the core process of patterning the metal film layer with an acidic etching solution in the TFT manufacturing process, and then forming the gate (Gate), source-drain (Source-Drain), and pixel (Indium Tin Oxides, ITO) electrodes. Among them, aluminum and molybdenum are often used as conductive materials to form gates. Various acids can be used for the etching solution, but most of them use strong acid mixtures (phosphoric acid, nitric acid, and glacial acetic acid) to dissolve and redox them. Patterning of the gate film layer. [0003] The composition of the mixed acid of the etching solution is generally phosphoric acid (70-72%), nitric acid (1.8-2.0%), and acetic acid (9.5-10.5%). Among them, nitric acid plays the role of providing H 3 o + The role ...

AI Technical Summary

Problems solved by technology

Over time, a lingering acid mist will be formed in the negative pressure closed system of the online optical concentration measurement mechanism, and the acid mist will affect the absorption of light and then affect the surface of the sample cell 230 or reference cell 240. Measured value of acid concentration

That is, the measured acid concentration will be lower or higher than the actual value, resulting in too much or insufficient acid replenishment in the acid replenishment system, and eventually the acid concentration in the etching solution will be too high or too low, resulting in large batches of bad etching and rework Repair, causing significant loss to production

In practical application, in order to overcome this atomization phenomenon, it is necessary to regularly disassemble the online optical concentration measuring mechanism or wipe the measuring pool, which not only destroys the precision of the measuring mechanism, but also damages the online optical concentration measuring mechanism after reinstallation. It needs to be recalibrated before it can be put into use, which causes a lot of inconvenience to actual production

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