A 3D MEMS In-Chip Solenoid Inductor of High Inductance Density for Future Power-MEMS Device

摘要

In this paper, we report the design, fabrication, and measurement of a new type of 3D solenoid inductor that is embedded in the Si substrate. Inductors were fabricated with good structural integrity and repeatability by a CMOS-compatible MEMS fabrication process. Measurement results show the highest quality factor (37.6@21MHz) was found in a 5-turn inductor and the highest inductance and inductance density (86.6nH and 21.7nH/mm²) in a 20-turn inductor. An electromagnetic switch was built to test its performance and the inductor was also transferred into a flexible substrate (PDMS) to test its potential usage in the flexible/wearable device. This type of inductor may have potential application prospects in Power-MEMS devices and can improve the power density and efficiency on those devices.