Method of manufacturing MEMS device

A method of manufacturing an MEMS device, the method comprising:

• forming a covering structure having an MEMS structure and a hollow portion, which is located on a periphery of the MEMS structure and is opened to an outside, on a substrate, the MEMS structure including a movable electrode facing a fixed electrode through a gap between the movable electrode and the fixed electrode, the gap being filled by a first sacrifice layer;
• performing surface etching for the MEMS structure by supplying an etching gas to the periphery of the MEMS structure from the outside that removes the first sacrifice layer from the gap between the movable electrode and the fixed electrode;
• and
• performing a test on operating characteristics of the MEMS structure and determining whether to perform additional surface etching by comparing a result of the test with a reference value, after the forming of the covering structure on the substrate,
• wherein the step of performing the test on operating characteristics is performed in parallel with the surface etching during the step of performing surface etching for the MEMS structure, and
• wherein the surface etching is stopped when the operating characteristics correspond to a range corresponding to the reference value.