On-chip inductors are critical for enabling portable power-efficient wireless communication systems. Existing on-chip spiral inductors based on conventional planar integrated-circuit fabrication technology suffer from substrate loss and parasitics, and have relatively large footprints. In this paper, we discuss the development of two types of on-chip three-dimensional (3-D) inductors—a vertical...

Extensive experimental results for various square spiral inductors on GaAs substrate are presented in this paper. Through detailed studies of the inductances extracted from the de-embedded onchip measured S-parameters, the relationships between the electrical characteristics and the geometrical parameters of the spiral inductors are revealed. Based on the curve fitting technique, a behavioral m...

This thesis contributes to the computer-aided design (CAD) of spiral inductors and LC resonators with spiral inductors exploiting full-wave electromagnetic (EM) analysis. The spiral inductor is widely used in radio frequency integrated circuits (RF ICs), such as low noise amplifiers (LNA) and voltage controlled oscillators (VCO). The design of spiral inductors has a direct influence on the perf...

This paper formulates various quality ( ) factors associated with the applications of on-chip spiral inductors to radiofrequency integrated circuits using -parameters. The formulations start with the factor of a spiral inductor in a generalized two-port configuration based on a new complex-power approach and then extend to the factors of a tank and matching circuits that use the spiral inductor...

Extensive experimental results and detailed investigations of the performance of on-chip circular double-spiral stacked inductors on silicon substrates are presented. Based on a proposed equivalent circuit model and measured S-parameters using the de-embedding technique, the inductance L, resonant frequency fres, Q-factor, coupling capacitance between the upper and lower spirals, and oxide capa...

Inductive power transfer is the most common method for transferring power to implantable sensors inside human body. For good inductive coupling, the inductors should have high inductance and high quality factor. But the physical dimension of the receiver inductor cannot be large due to biomedical constraints. Therefore, there is a need for small size and high inductance, high quality factor ind...

This paper presents the design and modeling, fabrication and characterization of suspended spiral inductors on silicon substrate. The substrate materials underneath the inductor coil are removed by micromachining process to reduce the substrate loss which enables high frequency operation. A complete Library of spiral inductors with different line width, line spacing and number of turns have bee...

This paper presents a physical model for planar spiral inductors on silicon, which accounts for eddy current effect in the conductor, crossover capacitance between the spiral and center-tap, capacitance between the spiral and substrate, substrate ohmic loss, and substrate capacitance. The model has been confirmed with measured results of inductors having a wide range of layout and process param...

This paper proposes an optimization methodology of on-chip spiral inductors. Characteristics of spiral inductors heavily depend on layout structures. We then formulate the characteristics with structural parameters and frequency as variables using a response surface method. The proposed method uses S-parameters to express inductor characteristics, and hence our method is independent of spiral g...

A silicon micromachining method has been developed to fabricate on-chip high-performance suspended spiral inductors. The spiral structure of an inductor was formed with polysilicon and was suspended over a 30m-deep cavity in the silicon substrate beneath. Copper (Cu) was electrolessly plated onto the polysilicon spiral to achieve low resistance. The Cu plating process also metallized the inner ...