Maute M., Kimmerle S., Franz J., Hauer J., Schubert D., Krauss H.-R., Kern D.P.
Robert Bosch GmbH, DE
Keywords: accelerometer, CV-characteristic, micromachining, parameter extraction
This paper presents a novel methodology for the extraction of process dependent geometrical parameters of surface micromachined sensors. This approach is based on the electrical measurement of static capacitance-voltage characteristics of the sensor element on wafer level. This extraction technique is demonstrated using a surface micromachined inertial accelerometer: a) The measurement of the capacitance-voltage characteristic (CV-characteristic) for lateral actuation of the suspended proofmass results in the extraction of a parameter related both to the thickness of the functional polysilicon layer and the lateral sidewall overetch due to the etch process of the polysilicon [1]. b) For vertical actuation of the proofmass, measurements of CV-characteristics lead to an extracted parameter that is proportional to the sidewall difference angle of the beam cross-section.
Journal: TechConnect Briefs
Volume: 1, Technical Proceedings of the 2001 International Conference on Modeling and Simulation of Microsystems
Published: March 19, 2001
Pages: 406 - 409
Industry sector: Sensors, MEMS, Electronics
Topic: Modeling & Simulation of Microsystems
ISBN: 0-9708275-0-4