Abstract — This paper presents a patterned ground shield inserted between an on-chip spiral inductor and silicon substrate. The patterned ground shield can be realized in standard silicon technologies without additional processing steps. The impacts of shield resistance and pattern on inductance, parasitic resistances and capacitances, and quality factor are studied extensively. Experimental results show that a polysilicon patterned ground shield achieves the most improvement. At 1–2 GHz, the addition of the shield increases the inductor quality factor up to 33 % and reduces the substrate coupling between two adjacent inductors by as much as 25 dB. We also demonstrate that the quality factor of a 2-GHz vg tank can be nearly doubled with a shielded inductor. Index Terms — Inductor, inductor model, patterned ground shield, quality factor, self-resonance, substrate loss, substrate noise coupling. I.

Abstract—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 parameters. This scalable inductor model enables the prediction and optimization of inductor performance. Index Terms—Eddy currents, inductor model, on-chip inductors, quality factor, self resonance, substrate loss. I.

A highly accurate, analytic quasi-static model of a microstrip over a semiconductor layer has been developed. The model agrees with full-wave calculations in all three modes of propagation (skin-effect, slow wave, and dielectric quasi-TEM), for both the attenuation constant α and the propagation constant β over a very wide range of dimension, substrate conductivity, and frequency. To achieve this level of agreement, a non-uniform cross-section, transverse resonance technique has been applied to find the series impedance per unit length of the microstrip transmission line. I.

This paper presents a physical model for planar spiral inductors on silicon. The model has been confirmed with measured and published data of inductors having different geometric and process parameters. This model is scalable with inductor geometry, allowing designers to predict and optimize the quality factor. INTRODUCTION Interest in monolithic spiral inductors has surged with recent growing demand for Si-based RF communication circuits [1]. Although promising experimental results [2][3] have been reported, basic understanding of the performance limitations and procedures for optimizing the quality factor, Q, are lacking. A scalable physical model that can accurately predict the behavior of inductors with different structural parameters over a broad range of frequency would be a valuable RF IC design tool. Each element of the model should be consistent with the physical phenomena occurring in the part of the structure it represents. In particular, the physical model should account...

This paper presents a physical model for planar spiral inductors on silicon. The model has been confirmed with measured and published data of inductors having different geometric and process parameters. This model is scalable with inductor geometry, allowing designers to predict and optimize the quality factor. INTRODUCTION Interest in monolithic spiral inductors has surged with recent growing demand for Si-based RF communication circuits [1]. Although promising experimental results [2][3] have been reported, basic understanding of the performance limitations and procedures for optimizing the quality factor, Q, are lacking. A scalable physical model that can accurately predict the behavior of inductors with different structural parameters over a broad range of frequency would be a valuable RF IC design tool. Each element of the model should be consistent with the physical phenomena occurring in the part of the structure it represents. In particular, the physical model should account...