Low Noise-Figure P+ AA Mesh Inductors for CMOS UWB RFIC Applications
Journal
IEEE Transactions on Electron Devices
Journal Volume
55
Journal Issue
12
Pages
3542-3548
Date Issued
2008
Author(s)
Abstract
In this paper, we demonstrate that the noise figure (NF) of a P + active-area (AA) mesh inductor is much better than that of its standard version. In a P + AA mesh inductor, the AA with P + implantation is added beneath it in the shape of a mesh to reduce its capacitive and magnetic coupling with the silicon substrate. Two 3.1-10.6-GHz CMOS ultrawideband (UWB) low-noise amplifiers (LNAs), one with P + AA mesh inductors (AA mesh UWB LNA) and the other with standard inductors (STD UWB LNA), are implemented to study the effect of the P + AA mesh on their performances. The results show that a 0.62-dB improvement in NF (from 0.8 to 0.18 dB) was achieved at 10.5 GHz for the input inductor LG 1 if the P + AA mesh had been added beneath it. In addition, the AA mesh UWB LNA achieved a low and flat NF of 3.365 plusmn 0.225 dB over the band of interest, notably better than that (4.64 plusmn 0.52 dB) of the STD UWB LNA.
Type
journal article