An advanced method of control of the electric charge accumulation during low energy implantation into insulators has been demonstrated using a collimator/ secondary electron-suppressor /neutralizer device [1]. The basic idea is to neutralize the insulator sample by means of the secondary electrons emitted by the collimator. For comparison, neutralization using hydrogen partial pressure was also investigated. A comparison between these two methods shows that the former has a neutralization efficiency greater than 96% and a very good implantation homogeneity, whereas neutralization remains below 5% for the latter. Both methods were implemented in two different implanters with the sample either incorporated into a Faraday cup (1) or outside the Faraday cup (2). The neutralization efficiency on the insulator samples was characterized by the ERD-ExB technique. Simulations by means of both electrostatic and newly developed dynamic codes (Poisson Superfish [2] and SINTIE) clearly indicate the effect of the electric field created around the sample on the ion and electron trajectories with and without neutralization. Thus, by comparing experimental results to model calculations, we have demonstrated that this technique can be effectively used for the neutralization of electric charges during ion implantation on insulators.

[1] M. Yedji, G.G. Ross / Nucl. Instr. and Meth. in Phys. Res. B 230 (2005) 386-390.

[2] Ron F. Holsinger, in collabration with Klaus Halbach. 7.15 released 2005 by James H. Billen and Lloyd M. Young, Los Alamos Laboratory, New Mexico USA.