Toward Inertial Navigation on Chip : the Physics and Performance Scaling of Multi Degree of Freedom Resonant MEMS Gyroscopes This thesis develops next generation multi degree of freedom gyroscopes and inertial measurement units (IMU) using micro electromechanical systems (MEMS) technology. It covers both a comprehensive study of the physics of resonator gyroscopes and novel micro nano fabrication solutions to key performance limits in MEMS resonator gyroscopes. Firstly theoretical and experimental studies of physical phenomena including mode localization nonlinear behavior and energy dissipation provide new insights into challenges like quadrature errors and flicker noise in resonator gyroscope systems. Secondly advanced designs and micro nano fabrication methods developed in this work demonstrate valuable applications to a wide range of MEMS NEMS devices. In particular the HARPSS+ process platform established in this thesis features a novel slanted nano gap transducer which enabled the first wafer level packaged single chip IMU prototype with co fabricated high frequency resonant triaxial gyroscopes and high bandwidth triaxial micro gravity accelerometers. This prototype demonstrates performance amongst the highest to date with unmatched robustness and potential for flexible substrate integration and ultra low power operation. This thesis shows a path toward future low power IMU based applications including wearable inertial sensors health informatics and personal inertial navigation Chapter1: Introduction Chapter2: The physics of resonant mems gyroscopes Chapter3: Bias control in pitch and roll gyroscopes Chapter4: Scale factor enhancement Chapter5: Integrated inertial measurement unit Chapter6: Bias stability limit in resonant gyroscopes Chapter7: Conclusions and future work