Construction and performance of a low energy ion gun

Abstract

We report the conversion of a conventional high energy ion gun into a low energy ion gun. The conversion procedure described here maintains the ion current capability of the high energy gun along with its good spatial and ion energy distribution characteristics. Several low energy ion guns have been described previously in the literature [J. T. Yates, Jr., Experimental Innovations in Surface Science (Springer-Verlag-AIP, New York, 1998), pp. 307–329] but all require the construction of new ion optics, whereas this approach utilizes existing ion optics and electronic control capabilities of a commercial ion gun. This ion gun may be employed for studies where it is desired to use ions as reactive species without significant sputter damage of the target.

A low energy ion source for electron capture spectroscopy

“…The negative offset of about −20 eV is in good agreement with values reported in Ref. 10 for the same type of ionizer.…”

“…When a kinetic energy in the order of a few eV/q, q being the charge state, is required, the ions have to be decelerated before arriving at the target. As was shown by Popova et al 10 using a commercial sputter ion gun, deceleration to energies of a few eV can be achieved rather easily by floating the complete ion gun assembly on a negative potential, whereby the high energy ions that leave the source are decelerated towards the sample. In order to achieve a better control over the beam parameters such as energy spread, impact angle, and focus spot size, we followed a different approach, such that the ions are decelerated inside the lens system.…”

“…10 we decided to base our ion source on a commercially available sputter ion gun (SPECS IQE 12/38). The ion gun itself consists of two parts, the ionizer and the focusing lens system with two cylindrical elements and x-and y-deflection plate pairs.…”