Author : Yonghai Sun
Publisher :
ISBN 13 : 9780494438282
Total Pages : 69 pages
Book Rating : 4.4/5 (382 download)
Book Synopsis Design of Carbon Nanotube Based Field Emission Facility by : Yonghai Sun
Download or read book Design of Carbon Nanotube Based Field Emission Facility written by Yonghai Sun and published by . This book was released on 2008 with total page 69 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research is to build a prototype of a carbon nanotube (CNT)-based micro X-ray tube array, which can be used in a real-time cone-beam computed tomography (CT) scanner for cancer research. The X-ray tube array consists of an electron source, control grids, focusing electrodes, and an anode plate. All the experiments have been executed in an ultra high vacuum environment at a pressure of 10−7 Torr. A thin film consisting of multi-wall carbon nanotubes (MWNTs) was used as the electron source. A diode configuration was employed to test the field emission performance of the CNT thin film. The current density achieved was 1mA/cm2 at 10V/[mu]m. After the initial burn-in process, a relatively steady emission current was obtained for duration of 170 hours. The control grid was made of 25% opening space stainless steels mesh. Meshes with different wire diameters were tested in a triode structure, and some differences were observed. Multi-anode field emission tests and multi-tube electric field simulations were executed. Experiments and simulations have revealed crosstalk between pixels during field emission. Based on the above experiments and simulations, a signal pixel prototype has been fabricated and is being tested. Moreover, some potential optimizations that will be used in the second prototype are also discussed.