Thin‐oxide dual‐electron‐injector annealing studies using conductivity and electron energy‐loss spectroscopy

A process to deposit in situ a dual electron injector structure (DEIS) with 5‐nm SiO2 between two Si‐rich SiO2 (SRO) layers of ∼20 nm each has been developed. The excess silicon, as evaluated by Auger spectroscopy and Rutherford backscattering, was of the order of 15%–17%, in agreement with previously reported values under similar deposition conditions. Thin cross‐sectioned samples of DEIS structures, both as‐deposited and annealed at 1000 °C with Ar in an oxygen and water‐moisture‐free atmosphere, were examined by spatially resolved energy‐loss spectroscopy (EELS) in a scanning transmission electron microscope. The analysis has shown that the excess silicon is present either as nanometer‐sized silicon islands or as submicroscopic silicon oxides of varying stoichiometry resulting from intermediate oxidation states (i.e., Si+3, Si+2, and Si+1). Additionally, the thermal anneal at 1000 °C did not appear to have any effect on silicon island size of the SRO layer in contact with the silicon substrate. This su...