Effects of CMOS process fill patterns on spiral inductors

Spiral inductors with various metal fill-patterns under the spiral is fabricated with SOI CMOS technology and characterized up to 49 GHz. The impact of the fill on the inductor characteristics is found to be vend small and changes can be attributed to the increase of parasitic capacitance. A simple model is proposed that can accurately estimate the increase of capacitance. A simple model is proposed that can accurately estimate the increase of capacitance by the fill. Design guidelines for optimizing fill patterns are recommended. (C) 2003 Wiley Periodicals.