High-Frequency Performance Study of CNTFET-Based Amplifiers

This article details the design of single-and double-stage maximum gain and low-noise high-frequency amplifiers at 2.4 GHz using a compact carbon nanotube field-effect transistor model, which is initially calibrated with hysteresis-free experimental data from a technology suitable for high-frequency applications. Parameters of the compact model represent CNTFETs with maximum high-frequency gain and reduced high-frequency noise by eliminating the metallic tubes contribution. Studies on linearity of the amplifiers as well as the impact of the quality factor of the inductors used in the stabilization network and the density of the nanotubes on amplifier performance are presented. Results of RF amplifiers show that CNTFETs are credible contenders for developing applications in S-band because of their gain (around 12 dB for a double-stage gain design), low noise (NF_min = 1.5 dB for a single-stage LNA) and linearity performance (OIP₃ around 15 dBm for a single-stage gain amplifier design).