Comparison of GaP and PH3 as dopant sources for STM-based device fabrication

摘要

We present a comparative study of the use of a GaP solid source as an alternative to gaseous PH3 for controlled phosphorus delta-doping of lithographic patterns on H:Si(001) fabricated by scanning tunnelling microscopy (STM). Whilst our electrical studies show that P d-doping of Si with the GaP solid source and gaseous PH3 result in essentially the same electrical characteristics, our STM studies reveal that P-2 molecules from the GaP source exhibit a lower selectivity between bare Si(001) and H:Si(001) compared to PH3 molecules. We discuss the significance of our findings in the context of fabricating nanoscale P dopant devices in Si using STM-based lithography.