Development of ultrahigh vacuum floating-type low-energy ion gun with differential pumping facilities for high-resolution depth profiling

摘要

An ultrahigh vacuum floating-type low-energy ion gun (UHV-FLIG) with a differential pumping system was developed. The developed UHV-FLIG ensured high ion current densities of similar to45 and similar to20 muA cm(-2) for Ar+ ions of 300 and 100 eV, respectively, under the UHV condition of the analysis chamber below similar to4 x 10(-6) Pa. The application of the developed UHV-FLIG to Auger electron spectroscopy (AES) sputter depth profiling of a GaAs/AlAs superlattice material revealed that the ultimate high depth resolution of similar to1.0 nm was achieved by sputter etching using 100 eV Art ions. The present results confirmed that lowering the primary energy of Art ions to 100 eV is still significantly effective for achieving higher depth resolution in sputter depth profiling. Copyright (C) 2005 John Wiley Sons, Ltd.