OCTAHEDRAL-STRUCTURED GIGANTIC PRECIPITATES AS THE ORIGIN OF GATE-OXIDE DEFECTS IN METAL-OXIDE-SEMICONDUCTOR LARGE-SCALE-INTEGRATED CIRCUITS

Analysis by TEM-energy-dispersive-X-ray-spectroscopy indicates that th e majority of the octahedral structure found just under the oxide defe ct with Czochralski Si is void. This is contrary to previously reporte d results suggesting that the octahedral structures found in Si bulk a re filled with amorphous SiO2. We investigate three models to explain our results. The Brst model, which we think most probable, suggests th at the void formation occurs during Si crystal growth. The second mode l indicates that octahedral structures full of SiO2 are formed during Si crystal growth and, after wafer slicing, much of the SiO2 is remove d. The third model suggests that the void is formed during copper deco ration. We show some experimental results that are inconsistent with t he second and third models.