Theoretical and Experimental Broadband Characterisation of Multiturn Square Spiral Inductors in Sandwich Type GaAs MMICs

Multiturn rectangular spiral inductors in GaAs MMICs have been characterised theoretically and experimentally. The theoretical description developed is suited for layout-oriented CAD. It uses a rigorous multi strip analysis for the spiral substructures combined with a network approach and corrections for three-dimensional effects. Good agreement is obtained with corresponding broadband S-parameter measurements. A detailed consideration indicates that the modelling accuracy achieved is in the order of magnitude of manufacturing reproducibility.