Use of high aspect ratio coils for RF inductors

This paper presents an investigation into the use of high aspect ratio conductors to improve the performance of RF inductors. Also presented is a review of commercially available technologies for RF chip inductors. The objective is to provide an analysis of the inductor parameters against which the high aspect ratio coils can be compared. A range of inductors from 10nH to 100nH in varying footprint areas is designed for fabrication using a novel rapid prototyping technique. High frequency (1GHz) 2-D and 3-D finite element modelling is used to provide an understanding of the behaviour of the high aspect ratio coils. Results from this analysis predict improvement of 15-30% in Q-factors compared planar equivalents.