Electrical critical dimension measurement method by integration of test structure into MEMS devices

An in-device electrical measurement method of critical dimensions (CD) width in MEMS devices is proposed. It alternates conventional critical dimension measurements by image taking apparatus, such as CD-SEMs. Integration of electrical critical dimension measurement test structures into MEMS devices enables us to measure critical dimension width of the working device. A method to remove the disturbance of the repeatability by joule heating, which is inevitable in electrical measurements, is proposed. By grace of the joule-heating disturbance elimination method, an extremely high repeatability (50nm for 5μm silicon structure, 1nm for 1.5μm aluminum structure) was obtained by a simple measurement using only multimeters.