CHARACTERIZATION OF MEMS ACCELEROMETERS AT LOW TEMPERATURES

• Autor(a) principal: Carvalho, Diogo Falcão Baptista Vilhena de
• Data de Publicação: 2022
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10362/162933
• topic: Microelectromechanical systems (MEMS); Inertial sensors; Characterization; Allan variance; Sensitivity; Cross-axis sensitivity; Domínio/Área Científica::Engenharia e Tecnologia::Nanotecnologia

MEMS accelerometers are micromachined inertial sensors that are used to measure accelerations. These devices, due to their versatility, can be used in different kinds of applications ranging from gravitational wave measuring to consumer based applications. MEMS accelerometers, can be impacted by a multitude of different sources and given that the scope of the project inserts itself in high performance devices which have to be able to withstand cryogenic temperatures for applications like gravitational waves measurements, extensive testing is paramount. Conducting these tests allows for a deeper insight on strategies that can further enhance the capabilities of these sensors. In the present work, characterization boards are developed and used to perform these tests at different sets of temperatures enabling a deeper understanding on how these conditions may affect the outputs of MEMS accelerometers. In tandem with this testing, a theoretical study on the device’s expected performance was conducted. Two sets of sensors were tested for their sensitivity, cross-axis sensitivity, noise floor and Allan variations at room temperature, 0 °C, -25 °C, -35 °C and -40 °C. The sensitivity dropped 75 % and 13.8 % for the developed and commercial board respectively. Crossaxis sensitivity increased 340 % and 536.36 %. Noise floors displayed a 22.7 % and 1.7 % decrease. As means to perform Allan variances, a matlab script was used.