Ultra-thick and high-aspect-ratio nickel microgyroscope using EFAB (TM) multi-layer additive electroforming

Alper, SE
Ocak, IE
Akın, Tayfun
This paper presents a 240 mu m-thick nickel microgyroscope with a lateral aspect ratio greater than 100, fabricated using the EFAB (TM) commercial multi-layer additive electroforming process. The fabricated gyroscope demonstrates a measured mechanical sensitivity of 65 mu V/(deg/sec) and a noise-equivalent rate of 0.086deg/sec at atmospheric pressure in a measurement bandwidth of 1Hz, using a capacitive interface circuit constructed from off-the-shelf components. The gyroscope's measurement bandwidth approaches to 100Hz. The variation of the drive-mode resonance frequency is measured to be better than 0.1% within 40 hours period, demonstrating the reliability of the electroformed nickel of the EFAB (TM) process. The gyroscope is sensitive to rotations about an in-plane axis, and therefore, allows implementation of a two-axis rate sensor on the same substrate.
19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006)


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Citation Formats
S. Alper, I. Ocak, and T. Akın, “Ultra-thick and high-aspect-ratio nickel microgyroscope using EFAB (TM) multi-layer additive electroforming,” presented at the 19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006), Istanbul, TURKEY, 2006, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/53311.