Patent ID: 11869774
Assignee: CHANGXIN MEMORY TECHNOLOGIES, INC.
Field: Semiconductors (Electrical engineering)
Classification: CPC H  C | IPC C  H

Claim 5:
6. The method for improving the etching rate of wet etching according to claim 4, further comprising:
inputting pH of the etchant determined by the pH meter to the controller, and comparing pH of the etchant determined by the pH meter with an initial pH value of the etchant by the controller;
when a comparison result is that pH of the etchant is dropped by more than 0.5, the controller controls the solenoid valve to be opened, and the water is injected into the etchant storage chamber to dilute the hydrogen ion concentration and fluoride ion concentration in the etchant storage chamber; and
when the comparison result is that pH of the etchant is dropped by less than 0.5, the controller controls the solenoid valve to be closed, and the water supply mechanism stops injecting the water into the etchant storage chamber.