ANALYSIS, DESIGN, AND OPTIMIZATION OF SPIRAL INDUCTORS AND TRANSFORMERS FOR SI RF ICS

Silicon integrated circuit spiral inductors and transformers are analy zed using electromagnetic analysis. With appropriate approximations, t he calculations are reduced to electrostatic and magnetostatic calcula tions. The important effects of substrate loss are included in the ana lysis, Classic circuit analysis and network analysis techniques are us ed to derive two-port parameters from the circuits. From two-port meas urements, low-order, frequency-independent lumped circuits are used to model the physical behavior over a broad-frequency range. The analysi s is applied to traditional square and polygon inductors and transform er structures as well as to multilayer metal structures and coupled in ductors, A custom computer-aided-design tool called ASITIC is describe d, which is used for the analysis, design, and optimization of these s tructures. Measurements taken over a frequency range from 100 MHz to 5 GHz show good agreement with theory.