| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a substrate processing device which makes possible to solve the problem that successive execution of a nitride film etching process on substrates by use of phosphoric acid aqueous solution raises the concentration of silicon in the phosphoric acid aqueous solution, which results in the reduction in etching rate.SOLUTION: A substrate processing device performs the steps of: dropping a phosphoric acid aqueous solution after a nitride film etching process onto a deposition plate 53, thereby cooling the phosphoric acid aqueous solution and thus, causing silicon oxide-containing impurities in the phosphoric acid aqueous solution to deposit on the deposition plate 53; moving the deposition plate 53 to a cleaning position; and then, performing a cleaning process with a hydrofluoric acid aqueous solution. In this way, the silicon concentration can be reduced while keeping the hydrofluoric acid from mixing in the phosphoric acid aqueous solution.</p> |
