Effect of Silicon Substrate Resistivity on Large-Area High Voltage Spiral Inductor Performance

In this work, we compare the performance of a large square spiral inductor with an area of 1.08×1.08 mm
²
and an operating frequency of a few hundred MHz, integrated atop four different types of silicon substrates. Measured and simulated results show that the high-resistivity (HR) substrate with a trap-rich (TR) layer yields significantly better performance in terms of quality factor, resonant frequency, self-inductance, and substrate capacitance than the HR or standard Si ones. These results approach those simulated for the same structure suspended on a MEMS membrane. Moreover, the inductor characteristics exhibit good stability under a back-contact voltage varying between -100 V and +100 V in the HR-TR case.