DC modeling and the source of flicker noise in passivated carbon nanotube transistors

Sunkook Kim, Purdue University - Main Campus
Seongmin Kim, Birck Nanotechnology Center, Network for Computational Nanotechnology, Purdue University
David B. Janes, Purdue University
Saeed Mohammadi, School of Electrical and Computer Engineering, Purdue University
Juhee Back, University of Illinois at Urbana-Champaign
Moonsub Shim, University of Illinois at Urbana-Champaign

Date of this Version



Nanotechnology, Volume 21, Number 38

This document has been peer-reviewed.



DC and intrinsic low-frequency noise properties of p-channel depletion-mode carbon nanotube field effect transistors (CNT-FETs) are investigated. To characterize the intrinsic noise properties, a thin atomic layer deposited (ALD) HfO2 gate dielectric is used as a passivation layer to isolate CNT-FETs from environmental factors. The ALD HfO2 gate dielectric in these high-performance top-gated devices is instrumental in attaining hysteresis-free current-voltage characteristics and minimizes low-frequency noise. Under small drain-source voltage, the carriers in the CNT channel are modulated by the gate electrode and the intrinsic 1/f noise is found to be correlated with charge trapping/detrapping from the oxide substrate as expected. When thermionic emission is the dominant carrier transport mechanism in CNT-FETs under large drain-source voltages, the excess 1/f noise is attributed to the noise stemming from metal-CNT Schottky barrier contacts as revealed by the measurements.


Engineering | Nanoscience and Nanotechnology