Thin GaS films deposited on B-doped diamond (as-grown) and on oxygen-anneal
ed B-doped diamond (O-ann.) films grown by plasma-assisted chemical vapor d
eposition (CVD) on p+-type Si(001) substrate have been characterized by Aug
er electron spectroscopy (AES), low-energy electron-loss spectroscopy (LEEL
S), and X-ray photoemission spectroscopy (XPS). The thermal evaporation of
GaS single crystal is used for the deposition. At low primary electron ener
gies (E-p less than or equal to 200 eV), the loss spectra are dominated by
surface-related structures, and oxygen anneal removes the damaged surface l
ayers of as-grown films. At high E-p (500 eV), surface- and bulk-plasmon pe
aks of diamond are observed to be dominant in the LEELS spectra for both as
-grown and O-ann. films. After the deposition of GaS, some new loss peaks d
ue to GaS appeared in the LEELS spectra for both as-grown and O-ann. films.
XPS spectra indicate upward band bending due to GaS deposition compared to
that of O-ann. films and slightly downward band bending compared to that o
f as-grown films.