| With the development of wireless telecommunication systems, high-performance on-chip RF (radio frequency) passive components are required. However, on-chip RF passive components based on IC (integrated circuit) technology suffer from excessive substrate loss and parasitics and thus cannot meet the requirements of performance. In recent years, MEMS (microelectromachanical systems) technology has been applied to develop novel on-chip RF passive devices with better performance. However, this effort is just beginning, and there are still many important issues which need to be further investigated.; The work in this thesis focuses on the development of two of the most fundamental on-chip RF passive devices (tunable capacitors and inductors) using micromachining technology. First, a new wide-tuning-range tunable capacitor design is proposed and prototype devices are fabricated using surface micromachining technology. This new tunable capacitor has the advantages of simple configuration, IC-compatible fabrication process, low loss, and wide tuning range. Second, a novel three-dimensional (3-D) microstructure assembly technique, Plastic Deformation Magnetic Assembly (PDMA), is developed, which is compatible with the standard IC fabrication process and capable of addressing batch-scale assembly with high yield and good controllability. Using PDMA, on-chip vertical spiral inductors are demonstrated. Vertical spiral inductors have almost zero footprints and have much higher quality factors and self-resonance frequencies than their horizontal counterparts due to reduced substrate loss and parasitics. On-chip solenoid inductors with different windings are also demonstrated using PDMA. |
