Grinding device for shallow trench isolation process and using method of grinding device

The present invention discloses an apparatus for polishing the shallow trench isolation process, including the machine, the machine table is mounted in a polishing system is connected with a control system, further comprising an etching system, and connected to the control system; further comprises a measurement system, connected to the control system; the system further comprises a parameter conversion, and measurement systems are connected. Etching and removing one kind of step height measuring method of realization, wherein, in said shallow trench isolation process is carried out polishing apparatus, comprising the steps of: providing a substrate, the substrate from the bottom covered with a buffer layer, a mask layer , in the trench and on the surface of the substrate is filled with a film thickness of said oxide film, an oxide measurement; mechanical polishing process of the substrate; thickness measurements of the oxide film after polishing; etching of masking layer process; removing the mask layer on the substrate step height measurements. The present invention simplifies the equipment and processes to eliminate the effects of different machine status and handling of the wafer caused.