Low-noise monolithic oscillator with an integrated three-dimensional inductor
A balanced silicon BiCMOS oscillator using self-assembled curled circular spring 3D inductor with peak Q of 40 reduces phase noise by 12.3dB at 100kHz offset compared to conventional planar spiral inductor approach. The addition of a 5µm copper underlayer raises Q to 85 and should improve the noise spec by up to 6dB.
Van Schuylenbergh, K. ; Griffiths, B.; Chua, C. L. ; Fork, D. K. ; Lu, J. P. Low-noise monolithic oscillator with an integrated three-dimensional inductor. IEEE Solid State Circuits Conference (ISSCC 2003); 2003 February 9-13; San Francisco, CA; Digest of Technical Papers, 392-393, 501. (ISSCC 2003 Lewis Winner Outstanding Paper Award)