Temperature-Dependence of the Q-Factor and Noise Figure Performances of a Spiral Inductor with an Advanced Mixed-Signal/RF Complementary Metal–Oxide–Semiconductor Technology

Abstract

In this paper, we demonstrate an analysis of the effect of temperature (from -50°C to 200°C) on the quality factor (Q-factor) and noise figure (NF) performances of a spiral inductor with an advanced mixed-signal/RF complementary metal–oxide–semiconductor (CMOS) technology for the first time. Q-factor and power gain (GA) decrease with increasing temperature but show a reverse behavior within a higher frequency range, while stability factor (K-factor) and NF increase with increasing temperature but show a reverse behavior within a higher frequency range. The reverse frequencies fR's, which correspond to the zero temperature coefficients of GA, K-factor, and NF, are almost the same. This phenomenon can be explained by the positive temperature coefficients of the metal series resistance (Rs) and the substrate impedance (Zsub). The present analysis enables RF engineers to understand more deeply the NF (i.e. power loss) behavior of inductors fabricated on a silicon substrate, and hence is helpful for them to design less temperature-sensitive fully on-chip low-noise-amplifiers (LNA's) and other radio-frequency integrated circuits (RF-IC's).