AUGER AND ELECTRON-ENERGY LOSS SPECTROSCOPY STUDIES OF AIN AND (AIN)X(AL2O3)1-X THIN-FILMS

Electron energy loss spectroscopy (EELS), Auger analysis and Auger line shape measurements were used to study composition and bonding in thin films of varying Al:N:O ratios grown by reactive magnetron sputter deposition. The films deposited in the presence of oxygen in addition to nitrogen or ammonia in the plasma are apparently composed of both AlN and Al2O3. There is no evidence for other bonding configurations. In accordance, the observed ionicity of the Al-N and Al-O bonds is the same as in the respective single-phase films. The AlN and Al2O3 phases are clearly distinguished by their Al(LVV) signals, but not by the respective Al(KLL) transitions. A relative sensitivity factor of Al(KLL) in the AlN thin films at a primary energy of 3 keV was obtained from analyses of both AlN and (AlN)x(Al2O3)1-x. The same sensitivity factors of Al(KLL), N(KLL), and O(KLL) are adequate for analysis of both single- and two-phase films. The EELS in the 4-40 eV range at primary energies of 135 and 185 eV contain unresolved contributions from both AlN and Al2O3. Results are compared to those of Al2O3, thin films of oxidized and nitrided Al, and NO exposed Al(100) surface. Bonding at the latter surface appears to differ from that at the two-phase films. Charging and stability effects in the films are also discussed.