Inductance calculation of thick-metal inductors

In this paper, the analysis and modeling of thick-metal spiral inductors are addressed. The accuracy of a 2.5 D electromagnetic simulator is first validated by comparison with on-wafer experimental measurements. Simulation results are then employed to investigate the effect of metal thickening on inductor performance. The inductance decrease due to metal thickening is modeled by using a modified current-sheet expression. The proposed formula achieves higher accuracy compared to the original one revealing errors below 5% even for thickness-to-width ratio up to 2.5.