A Carbon Nanotube Field Emitter with a Triode Configuration for a Miniature Mass Spectrometer

Autor: Sangsik Yang, Nguyen Tuan Hong, Yuri Lee, Kijung Lee, Soonil Lee
Rok vydání: 2012
Předmět:
Zdroj: The Transactions of The Korean Institute of Electrical Engineers. 61:1001-1006
ISSN: 1975-8359
DOI: 10.5370/kiee.2012.61.7.1001
Popis: This paper presents a carbon nanotube (CNT) triode-structure field emitter as an ion source in a micro time-of-flight mass spectrometer(TOF-MS). In the ion source by field emission, the electrons emitted from cathodes under an electric field accelerated to the anode and ionize gas molecules by impact before arriving the anode. The generated positive ions are to be accelerated to the ion collector. Whereas most of ions are drawn to the cathodes in diode field emitters, a grid in the triode field emitter prevents the ions from being drawn to the cathodes. The triode field emitter is fabricated by micromachining. The cathode is composed of six CNT cylinders. The total size of the fabricated device is . The anode and the grid current of the fabricated CNT field emitter were measured for various anode and grid voltages. When the anode and the grid voltages are 1000 V and 990 V, respectively, the emission current passing through the ionization region is 8.6 , which is a sufficient emission current for ionization and mass spectrometry.
Databáze: OpenAIRE