Coincidence measurements of secondary ions and scattered ions in collision between slow Ar⁶⁺and a GaN(0001) surface

Selective Sputtering of Impurity Hydrogen Atoms from a GaN(0001) Surface by Slow Multicharged Ion Impact

“…7,9) However, the observed PS was not the dominant process because the number of scattered Ar þ ions was only 23% of that of all scattered Ar atoms/ions. 7) Therefore, it is very important to observe PS of protons by coincidence measurements of scattered Ar atoms, which are produced by the dominant scattering process.…”

“…The potential sputtering (PS) induced by slow multicharged ion impacts is increasingly attracting attention from this point of view, 5) because of its two features of sitespecific desorption and slight damage to the bulk. [6][7][8][9][10][11][12] The author succeeded in direct observation of PS of protons on the GaN surfaces irradiated with Ar 6þ by a coincidence measurement of scattered Ar þ ions. 7,9) However, the observed PS was not the dominant process because the number of scattered Ar þ ions was only 23% of that of all scattered Ar atoms/ions.…”

“…[6][7][8][9][10][11][12] The author succeeded in direct observation of PS of protons on the GaN surfaces irradiated with Ar 6þ by a coincidence measurement of scattered Ar þ ions. 7,9) However, the observed PS was not the dominant process because the number of scattered Ar þ ions was only 23% of that of all scattered Ar atoms/ions. 7) Therefore, it is very important to observe PS of protons by coincidence measurements of scattered Ar atoms, which are produced by the dominant scattering process.…”

“…The detailed experimental setup and procedure in this study are described elsewhere, [6][7][8] and are mentioned only briefly in this paper. Ar qþ ions with charge state q (4, 6, or 8) and kinetic energy E 0 (2:5 Â q keV) were irradiated tangentially onto a GaN(0001) (Ga face) surface at an angle of $10 with respect to the surface.…”

“…It is considered that these peaks are due to contaminants including the adsorbed hydrogen atoms/ molecules on the surface. Hydrocarbon ion peaks were assigned as 6,7) however, the number of hydrogen atoms bonding with the molecules was unresolved. A common feature in both the figures is that the relative intensity of hydrocarbon ion peaks compared with each proton peak decreases with an increase in the charge state q of the incident ions.…”