Microwave analysis of a 70 nm InGaAs pHEMT on InP substrate for nanoscale digital IC application

Abstract

A new charge‐control model for the microwave characteristics of an AlGaAs/InGaAs/InP HEMT of 70 nm gate length has been developed. The threshold voltage has been modified by the inclusion of mole fraction and thermal effects. The current voltage characteristics have been obtained and compared with the 70 nm gate length device. In order to avoid short‐channel effects, an aspect ratio (gate length to gate to channel distance) larger than 5 is maintained in the analysis. The small‐signal microwave parameters (gm, gd) have also been evaluated. 2‐D analysis has been carried out in the saturation region. The unity gain cut‐off frequency of the order of 220 GHz is obtained at a gate length of 70 nm. Device parameters so obtained were used to calculate the hemt Y‐parameters. The Y‐parameters hold from the threshold region to the edge of saturation. The unilateral gain so obtained from the Y‐parameters yield a closer fit to the numerical model. All the results have been compared with the experimental data and show a close agreement and the validity of our model. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2462–2470, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22779

Microwave Analysis for Two-Dimensional C-V and Noise Model of AlGaN/GaN MODFET

“…where is the gate width, is Boltzmann constant, is temperature, and ( ) is the field dependent electron mobility and is given [2] as…”

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Analysis of Small-Signal Parameters of 2-D Modfet with Polarization Effects for Microwave Applications

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