Radiation and Processing Induced Effects in SIMOX: A Spectroscopic Study

The SIMOX formation process has been studied with ESR, IR spectroscopy, and photoluminescence. Samples were implanted with doses from 0.5 × 1018/cm2 to 2.6 × 1018/cm2 and annealed at 600°C to 1275°C. The Pb and radiation induced E' centers were measured with ESR. By measuring the Pb concentration, it is shown that oxide precipitates are concentrated in the superficial silicon layer and that they coalesce into the buried oxide with annealing. The stoichiometry of the buried layer is examined with IR. At 600°C the stoichiometry, SiOχ, ranges from χ = 1.4 to χ = 1.6 depending upon the implant dose. The stoichiometry approaches that of thermal oxide, SiO2, at 1150°C and above. Photoluminescence from the D lines, caused by dislocations, is observed and the structural implications are discussed.