S. J. Pan

Performance Trends of on-Chip Spiral Inductors for Rfics

Performance trends varying with different geometrical parameters for on-chip spiral inductors: (a) with fixed inner-dimension, (b) with outer-dimension, and (c) variation in both inner- and outer- dimensions are extensively investigated in this paper. The relationships for the inductance, Q-factor and self-resonance frequency (SRF) with various geometrical parameters, such as track width, track spacing, and turn numbers are examined on an extensive experiment basis. These performance trends can be a good guideline for practical inductor designs in RFICs.

Comparative characteristics of on-chip single- and double-level square inductors

Detailed experimental investigations reported in this paper have determined the inductances, Q factors, and resonance frequencies of on-chip square, single-level (SL) and double-level (DL) inductors on silicon substrates, using the equivalent circuit model and the measured S parameters. Parametric studies show the effects of both strip length and inner empty area on the coupling capacitance and resonance frequency. Some scalable formulas are derived for extrapolating inductance and resonance frequency of other inductors. In the DL chips, very strong self-resonance can take place with lower resonance frequency, and the Q factor will be degraded rapidly.

Comparative characteristics studies on on-chip single- and double-level square inductors

Detailed experimental investigations are carried out in this paper to show the inductance, Q-factor as well as resonant frequency of on-chip square single- and double-level inductors on silicon substrates. Based on the equivalent circuit model developed and the S-parameters measured using a de-embedding technique, inductances, Q-factors and resonant frequencies of these inductors are determined and compared with one another. Parametric studies are carried out to show the effects of both strip length and inner empty area on the coupling capacitance and resonant frequency of these inductors, and some scalable formulas are derived for extrapolating inductance and resonant frequency of other inductors. It is demonstrated that in the double-level cases very strong self-inductor resonance can take place with lower resonant frequency, and Q-factor is degraded rapidly.

Electrical Characteristics and Behavioral Model of Spiral Inductors On Gaas Substrate

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 on-chip 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 model for spiral inductors is obtained and presented. Thus, the inductances of spiral inductors with an acceptable accuracy up to their first resonance frequencies are obtained.