Charge-state-resolved ion energy distributions of aluminum vacuum arcs in the absence and presence of a magnetic field

Abstract

The charge-state-resolved ion energy distributions ͑IEDs͒ of aluminum vacuum arc plasma species were measured and analyzed for different geometric and magnetic field configurations. The IEDs were fitted by shifted Maxwellian distributions. Plasma expansion in the absence of a magnetic field showed higher ion energies for higher charge states. The introduction of a magnetic field ͑independent of geometric configuration͒ resulted in a broader distribution and increased average ion energies. The energy gain was approximately proportional to the charge state, which may be due to the presence of electric fields in the magnetized plasma. The evolution of ion energy distributions is relevant to thin-film growth, and it is shown that the IEDs can be modified by suitable magnetic field configurations.

Influence of argon and oxygen on charge-state-resolved ion energy distributions of filtered aluminum arcs

“…6 It was found that the presence of a magnetic field drastically increased the ion energies. Here, the average ion energies at base pressure for Al 1+ , Al 2+ , and Al 3+ were found to be approximately 90, 180, and 260 eV, respectively.…”

“…This is consistent with previously reported measurements. 6 The introduction of an oxygen partial pressure of up to 7 mTorr resulted in decreased average energies of the metal ions and increased concentrations of the non-metal ions, the most abundant being O + , and O 2 + . The charge-state-resolved average ion energies are shown in Introduction of argon to a pressure of up to 8 mTorr led to a stronger reduction of the ion energies as compared to the previously discussed interaction with oxygen, see Fig.…”

“…Aluminum plasma, for example, contains ions with charge states of up to three, and the IEDs extend up to 250 eV. 6 It is known that through the introduction of background gas, these plasma properties can be influenced.…”

An introduction to thin film processing using high-power impulse magnetron sputtering

“…8 The HiPIMS plasma has also shown the presence of multiply charged ions for various target materials, 7,[41][42][43][44] which is rarely found in other types of magnetron discharges but often found in cathodic arc discharges. 45 One implication of having this type of ions is that they enable sustained self-sputtering, 6 meaning that they will sputter enough material for continued ionization and release enough secondary electrons to keep the plasma burning assuming that enough sputtered metal ions can be attracted back to the target. For high yield materials such as Cu this has led to the onset of self-sputtering regimes characterized by a second increase of the discharge current beyond the value of the initial peak current, if the pulse is sustained for a long enough time in combination with high negative discharge voltages.…”

Layer formation by resputtering in Ti–Si–C hard coatings during large scale cathodic arc deposition

“…Ti in arc plasmas is reported to have higher average kinetic energy (58,9 eV) compared to Si (34,5 eV) and C (18,7 eV) [1]. However, it should be noted that the ion energy distributions have an inherent high energy tail, up to hundreds of eV [23]. The average ion charge state in pulsed arc plasma follows the same trend, from Ti (2,03) and Si (1,39) to C (1,00) [1].…”