Title :
High current density ternary-alloy-film dispenser cathode for terahertz vacuum devices
Author :
Barik, R.K. ; Raju, R.S. ; Tanwar, A.K. ; Das, Supriyo ; Park, G.S.
Author_Institution :
Sch. of Electr. Eng. & Comput. Sci., Seoul Nat. Univ., Seoul, South Korea
Abstract :
Dispenser cathode is used in microwave tubes as source of electrons. We investigate high current density emission capabilities of alloy-coated cathodes used for terahertz vacuum devices. In this paper the developmental work carried out on ternary-alloy-film cathode (2Os:2Re:1W) and the results are presented. The cathodes were tested inside a closed spaced diode and also analytical chamber containing Auger Electron Spectroscopy (AES), Thermionic Emission Microscope (THEM) facility. Emission current densities measured in the diode structure at 1300° K temperature were above 60 A/cm2. The work function was found 1.72 eV using 73% slope method. To ensure the life of the cathode accelerated life test has been carried out in closed spaced diode at 1300° K temperature.
Keywords :
Auger electron spectroscopy; cathodes; life testing; microwave tubes; Auger electron spectroscopy; alloy-coated cathode; cathode accelerated life testing; density emission capability; microwave tube; temperature 1300 K; terahertz vacuum device; ternary-alloy-film dispenser cathode; thermionic emission microscope facility; voltage 1.72 V; Cathodes; Current density; Life estimation; Metals; Surface treatment; Temperature; Temperature measurement; Auger Electron Spectroscopy; Dispenser Cathode; Ternary-alloy coated Cathode;
Conference_Titel :
Vacuum Electronics Conference (IVEC), 2011 IEEE International
Conference_Location :
Bangalore
Print_ISBN :
978-1-4244-8662-5
DOI :
10.1109/IVEC.2011.5746866
