Material-related effects during ion beam treatment by an end-Hall ion source

Abstract Reproducibility and accuracy of dry etching processes are a challenge for the operators of end-Hall ion sources with hot filament (HF) neutralizer. The variation of the neutralization current I N , e.g. due to filament aging as well as the properties of the substrate material lead to changes in the resulting etch rate of the substrate. Therefore a special controller setup was developed to automatically neutralize the ion beam of an end-Hall ion source with HF by measurement of the substrate current and control of an introduced difference current (I D ). In this study, the influence of conductive (amorphous CuTi-film), semi-conductive (B-doped Si(100)) and non-conductive material (128°YX LiNbO 3 ) on I D is demonstrated. Additionally, the etch rate for a wide process regime (V A and I A ) for Si(100), the surface roughness for defined under- and overneutralization and the properties of the etched sidewalls were investigated. The effect of the gas distributor ring material on the etch rate is also shown.