A Microassembled Triangular-Prism-Shape Three-Dimensional Electric Field Sensor

This paper, for the first time, presents a microassembled three-dimensional (3D) electric field sensor (EFS), which is a chip-level compact triangular-prism-shape sensor consisting of X-, Y- and Z-axis electric field (EF) sensing chips. The proposed 3D EFS is fabricated on a silicon-on-insulator (SOI) die, introducing photosensitive polyimide (PSPI) into its micromachining process to produce flexible micro-hinges and make separate components into a foldable integrative structure. Interlocking latches are employed to ensure the orthogonality of the three sensing axes. Structures of each EF sensing chip are symmetrically designed for reducing cross-axis coupling interference, and good performances have been demonstrated by experiments.