High Current Cathodes Fabricated by KrF Laser Ablation

Journal Article · Fri Oct 08 00:00:00 EDT 2010 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3507098· OSTI ID:21436009

Gilgenbach, Ronald M; Lau, Y Y ^[1]; Jones, M C; Johnston, M D ^[2]; Jordan, N M ^[3]; Hoff, B W ^[4]

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1. Plasma, Pulsed-Power and Microwave Laboratory Nuclear Engineering and Radiological Sciences Department University of Michigan, Ann Arbor, MI 48109 (United States)
2. Sandia National Labs, Albuquerque, NM (United States)
3. Cybernet Systems, Ann Arbor, MI (United States)
4. Air Force Research Labs, Kirtland AFB, NM (United States)

In this paper we review several high power laser ablation techniques that have been utilized to fabricate high current (1-80 kA) electron beam cathodes for accelerators and microwave sources: 1) Projection Ablation Lithography (PAL) cathodes, 2) Ablation Line Focus (ALF) cathodes, and 3) Metal-Oxide-Junction (MOJ) cathodes. Laser-ablative micromachining techniques (PAL and ALF) have been utilized to generate micron-scale features on metal substrates that provide electric field (beta) enhancement for Fowler-Nordheim emission and plasma cathodes. Since these laser-ablated patterns are directly, laser-written on the substrate metal they exhibit much higher thermal conductivity for higher current capability and increased damage thresholds. Metal-Oxide-Junction (MOJ) cathodes exploit the triple-point electron emission that occurs at the interface between metal, insulator and vacuum.The ablation laser is a KrF excimer laser with a pulse energy of 600 mJ and pulselength of 20 ns. Cathode experiments were performed on the MELBA-C accelerator: V = -300 kV, pulselength = 0.5 microsecond. Data will be presented for PAL, ALF and MOJ cathodes.

• OSTI ID: 21436009
• Journal Information: AIP Conference Proceedings, Vol. 1278, Issue 1; Conference: International symposium on high power laser ablation 2010, Santa Fe, NM (United States), 18-22 Apr 2010; Other Information: DOI: 10.1063/1.3507098; (c) 2010 American Institute of Physics; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ABLATION
CATHODES
ELECTRIC CURRENTS
ELECTRIC FIELDS
ELECTRON BEAMS
ELECTRON EMISSION
HETEROJUNCTIONS
INTERFACES
KRYPTON FLUORIDE LASERS
LASER RADIATION
METALS
OXIDES
PLASMA
PULSES
SUBSTRATES
THERMAL CONDUCTIVITY
TRIPLE POINT
BEAMS
CHALCOGENIDES
CURRENTS
ELECTRODES
ELECTROMAGNETIC RADIATION
ELEMENTS
EMISSION
EXCIMER LASERS
GAS LASERS
LASERS
LEPTON BEAMS
OXYGEN COMPOUNDS
PARTICLE BEAMS
PHYSICAL PROPERTIES
RADIATIONS
SEMICONDUCTOR JUNCTIONS
THERMODYNAMIC PROPERTIES