Dimension effect on the performance of carbon nanotube nanobolometers

• Published in: Nanotechnology Vol. 25; no. 42; p. 425503
• Main Authors: Christianson, Caleb, Lu, Rongtao, Wu, Judy
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 24.10.2014; Institute of Physics
• Subjects: Applied sciences; carbon nanotube; Carbon nanotubes; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; dimension effect; Electronics; Exact sciences and technology; Fullerenes and related materials; Infrared; Infrared absorption; Materials science; Molecular electronics, nanoelectronics; nanobolometer; Nanocrystalline materials; Nanoscale materials and structures: fabrication and characterization; Nanostructure; Nanotubes; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Optimization; Optoelectronics; photoresponse; Physical properties; Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Surface chemistry; Visible and ultraviolet spectra; Optoelectronics; Electronic properties; Infrared detection; Carbon nanotubes; Physical properties; Nanoelectronics; Thin films; Surface effect; Energy gap; Adsorption; Detectors; Absorption spectra; Nanostructured materials; Figure of merit
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/0957-4484/25/42/425503

Carbon nanotube (CNT) film nanobolometers take advantages of high infrared absorption of CNTs, proving a promising alternative for low-cost, uncooled infrared detection. The performance of the CNT nanobolometers is determined by the optoelectronic process on CNTs at a microscopic scale, which links intimately to the diameter of the CNT-a critical parameter that intrinsically affects the band gap and hence infrared absorption, as well as extrinsically affects the surface oxygen adsorption effect and thermal-link of the CNT detector element to the environment. Both the intrinsic and extrinsic factors play important roles in the photoresponse, noise spectrum and the figure-of-merit detectivity D of the CNT nanobolometers and their interplay determines the device's ultimate performance. In this work, we present a systematic study of the effect of CNT diameter in the range of 1-50 nm on the physical properties relevant to CNT nanobolometers. The optimal CNT diameter was found to be in the range of 2-12 nm with the D up to 3.3 × 107 cm(Hz)1 2 W−1, which represents an order of magnitude improvement over the best D reported previously on CNT film nanobolometers.