I. Introduction
Complementary metal oxide semiconductor (CMOS) circuits became applicable to radio frequency (RF) bands in the advanced CMOS process technology. On-chip spiral inductors are key component to obtain high performance RF circuits. Higher Q value enables lower phase noise. The authors have tried to realize higher Q values of spiral inductors by using post processing of ion irradiation [1][2][3]. Electromagnetic simulation of the on-chip spiral inductors is very important for systematic design and improving performance. In this paper, electromagnetic simulation of a 2 nH spiral inductor in 5 GHz band is performed. Modeling of the CMOS substrate was key issue for proper simulation.