| This document describes the design and measurement of a series of spiral inductors fabricated on low resistivity (100cm) silicon, and a bias current tuned oscillator that incorporated one of the previously mentioned spiral inductors.;The inductors were designed and fabricated in three distinct ways: top metal only (basic inductors), top metal with an inter-winding trench (trench inductors), and top and second from top metal layers connected by vias along the length of the inductor (2-metal inductors). None of these fabrication methods required any post processing steps. Approximately ten of each inductor were measured. Results indicated that compared to the basic inductors the 2-metal spirals had inductances that were between 4% and 7% lower, and peak Q values that were between 4% to 18% lower. Measured results indicated the trench inductors had up to 5% higher Qs compared to the basic inductors. One octagonal trench inductor with a measured inductance of 0.45nH demonstrated a peak Q of 20 at 15GHz, which to the author's knowledge is the highest reported Q of a spiral inductor fabricated in a production silicon process.;The integrated oscillator designed and characterized in this work used bias currents to vary the transistor parasitic capacitances presented to the resonator to tune the oscillation frequency. The oscillator demonstrated a tuning range of 9.4--12.3GHz, a phase noise of -86dBrad/Hz at 1 MHz offset, a maximum output power of -3.3dBm, and second harmonic suppression of approximately 30dB. |
