Analysis of Deposits Evaporated from Sb-Doped Si Melts

To investigate the composition of oxygen-bearing species evaporated from Sb-doped Si melts, a carefully designed deposit collector was used. The collected deposits were analyzed by electron probe microanalysis (EPMA), gas fusion analysis (GFA), X-ray diffraction, and diffuse reflectance infrared (DR-IR) spectroscopy. The results showed that the compositions of the deposits depended on the temperatures of various regions within the collector. Different deposits, with various amounts of antimony oxide, silicon oxide, silicon, and antimony, were found in different temperature regions. In particular, it was discovered that antimony oxide was deposited only in the region where the temperature was lower than 450°C. Thus the present investigation gave evidence showing that oxygen depletion from Sb-doped Si melt probably arose from enhanced antimony oxide evaporation.