Design and fabrication of nano antenna for carbon nanotube infrared detector

Abstract

This paper reports on fabrication of a novel nanoscale antenna with carbon nanotubes (CNTs) based sensor for sensitive infrared detection. CNTs are used as sensing element for detecting both near and middle wave infrared. By using the nanoassembly of CNTs and standard photolithography processes, a nanosized antenna is designed and integrated to enhance the electric field intensity at the position of the sensing element creating a very sensitive infrared nanosensor. The efficiency of nano antenna was studied experimentally by measuring and comparing the photocurrent response of the sensor to one without the antenna. The photocurrent was increased 10 fold after integrating the nano antenna. This implies that the electric field in the vicinity of the detector is enhanced by the nano antenna. The proposed fabrication process enables easy and direct integration of the nano antenna into the manufacturing of infrared devices. Therefore, this opens the possibility of developing high fidelity infrared sensors with a wide sensing range. Moreover, a novel approach was employed to consider and include quantum effects in the analysis and design for the nano antenna, which uses the Green's function for finding the near field effect from the antenna. As a result, these effects were verified and demonstrated experimentally in this paper. © 2008 IEEE.