Characterization and modeling of microwave spiral inductors and transformers

Abstract

Radio frequency (RF) circuits fabricated by monolithic microwave integrated circuit technologies make extensive use of on-chip transmission lines to realize an inductance, the inductor being a key component in many high-performance circuit designs. In this project, several kinds of on-chip microwave spiral inductors are analyzed and modeled. Some novel circuit models and new predictions of the series resistance and inductance of general spiral inductors are presented for the first time. A new insight for the criteria of obtaining high Q-factor in symmetrical spiral inductors is discussed. Furthermore, a new equivalent circuit, which incorporates the effect of eddy current, for the two-layer spiral inductors is proposed. Finally, as applications for the spiral inductor, a slot antenna with spiral EBG-fed, a modified EBG Wilkinson power divider, and a new type of transformer based on the balun network, are designed and presented in this thesis.