Premium
High‐quality‐factor (33) and high‐resonant‐frequency (35 GHz) spiral inductors fabricated in 0.25‐μM mixed‐signal/RF‐CMOS technology
Author(s) -
Lin YoSheng,
Wu ShenHong,
Chiu HongWei,
Lu SheyShi
Publication year - 2004
Publication title -
microwave and optical technology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.304
H-Index - 76
eISSN - 1098-2760
pISSN - 0895-2477
DOI - 10.1002/mop.20117
Subject(s) - inductor , q factor , cmos , substrate (aquarium) , materials science , radio frequency , electrical impedance , optoelectronics , microwave , equivalent series resistance , electrical engineering , silicon , engineering , telecommunications , resonator , voltage , oceanography , geology
In this paper, we demonstrate a comprehensive analysis of the effects of the layout, temperature (from −50°C to 200°C), top‐metal‐layer thickness, and substrate impedance on the performances of high‐quality‐factor ( Q factor) and high‐resonant‐frequency ( f SR ) spiral inductors with 6‐μm‐thick top metal in 0.25‐μm CMOS technology for radio‐frequency integrated‐circuit (RF‐IC) applications. We found that Q factor decreases with increasing temperature but shows a reverse behavior at a higher‐frequency range, while NF increases with increasing temperature but shows a reverse behavior within a higher‐frequency range. This phenomenon can be explained by the positive‐temperature coefficients of the metal series resistance ( R s ) and the substrate resistance ( R sub ). In addition, the proton bombardment post‐process can largely increase the maximum Q factor ( Q max ) of the inductors, mainly due to the increase of substrate impedance. The present analysis enables RF engineers to understand more deeply the temperature and substrate impedance dependences of the spiral inductors fabricated on a silicon substrate. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 41: 276–279, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20117