An analysis of the kink phenomenon of scattering parameter S22 in RF power MOSFETs for system-on-chip (SOC) applications
Journal
Microwave and Optical Technology Letters
Journal Volume
36
Journal Issue
5
Pages
371-376
Date Issued
2003
Author(s)
Abstract
In this paper, the kink effect in scattering parameter S22 of RF power MOSFETs with drain-to-spacer offset is explained quantitatively for the first time. Our results show that for RF power MOSFETs the output impedance can be represented by a "shifted" series RC circuit at low frequencies and a "shifted" parallel RC circuit at high frequencies. The appearance of the kink point of S22 in a Smith chart is caused by this inherent ambivalent characteristic of the output impedance. It is found that an increase of drain-to-spacer offset enhances the kink effect. In addition, the kink effect in S22 of RF power MOSFETs can also be interpreted in terms of poles and zeros.
SDGs
Type
journal article