Multiply stripped ion generation in the metal vapor vacuum arc

Abstract

We consider the charge state distribution of ions produced in the metal vapor vacuum arc plasma discharge. A new kind of high current metal ion source in which the ion beam is extracted from a metal vapor vacuum arc plasma has been used to obtain the spectra of multiply charged ions produced within the cathode spots. The cathode materials used and the species reported on here are: C, Mg, Al, Si, Ti, Cr, Fe, Co, Ni, Cu, Zn, Zr, Nb, Mo, Rh, Pd, Ag, In, Sn, Gd, Ho, la, W, Pt, Au, Pb, Th, and U; the arc current was 200 A for all measurements. Charge state spectra were measured using a time-of-flight method. The arc voltage was also measured. In this paper we report on the measured charge state distributions and arc voltages and compare the distributions with the predictions of a theory in which ionization occurs in the cathode spots via stepwise ionization by electron impact.-2 -

Production of Mo+Beams Using an Arc Discharge Ion Source

“…Electron beam ion sources [9] especially with the high power evaporator/target heating systems seem also suitable for production of ions of non-volatile elements [10]. Very popular tools are dierent versions of high power MEVVA-type arc discharge ion source [11]. Recently, compact arc discharge ion sources equipped with an internal evaporator have been proposed [1215].…”

Novel metal ion surface modification technique

“…Cathode i.;aterials were yttrium and titanium; in the first experiment we simply implanted yttrium into silicon and in the second experiment we fabricated an yttrium-titanium multilayer structure with ion beam mixing at some of the interfaces. Previous work [14,15] has shown that the metal plasma generated in this way is multiply ionized, with mean charge state Q of 2.3 for yttrium and 2.1 for titanium. Thus, when implanted, the mean ion energy is greater than the applied pulse voltage by this factor.…”

Plasma Ion Source with an Internal Evaporator

“…This approach was successfully applied in our previous design [12,13], combining features of Nielsen [3] and metal vapor arc discharge (MEVVA [14]) ion sources. The molybdenum crucible, often called an evaporator, is surrounded by a spiral cathode.…”