Development of infrared sensors using Carbon Nanotube (CNT) based Field Effect Transistor (FET)

Hongzhi Chen, Ning Xi, King W.C. Lai, Carmen Kar Man Fung, Ruiguo Yang

Research output: Chapter in Book/Report/Conference proceedingConference contribution

2 Scopus citations


One dimensional (1D) Schottky diodes between metals and carbon nanotubes (CNTs) can separate the photo-generated electron-hole (e-h) pairs in order to produce photocurrent in the CNT infrared (IR) sensors for detection and quantification. However, the traditional Schottky barrier theories developed for the metal and planar semiconductor contacts are different from the contacts between metal and CNT owing to the unique properties originated from CNT's nano-scale size. Therefore how to optimize the performance of the 1D Schottky photodiodes is still a mystery. The properties of the 1D Schottky diodes are determined by the energy alignment between metals and CNT. In order to improve our understating of its working principle, we not only used different metals to explore the role of metal work function, but also investigated the performances of the photodetectors by varying the Fermi levels of the CNT through electrostatic doping utilizing the gate from CNT field effect transistor (CNTFET). It was observed that a low work function metal electrode (Cu) based photodetector can render a higher on/off ratio than its high work function contender (Au) by suppressing the dark current with a higher barrier. It was also demonstrated photocurrent was maximized by selecting high built-in potential and moderate doping using the CNTFET. CNTs may become important building blocks for future nano-optoelectronic sensors.

Original languageEnglish (US)
Title of host publicationIEEE Sensors 2009 Conference - SENSORS 2009
Number of pages5
StatePublished - 2009
Externally publishedYes
EventIEEE Sensors 2009 Conference - SENSORS 2009 - Christchurch, New Zealand
Duration: Oct 25 2009Oct 28 2009

Publication series

NameProceedings of IEEE Sensors


OtherIEEE Sensors 2009 Conference - SENSORS 2009
Country/TerritoryNew Zealand

ASJC Scopus subject areas

  • Electrical and Electronic Engineering


Dive into the research topics of 'Development of infrared sensors using Carbon Nanotube (CNT) based Field Effect Transistor (FET)'. Together they form a unique fingerprint.

Cite this