Structural and Chemical Microanalysis of Oxygen-Bearing Precipitates in Silicon

Abstract

ABSTRACTPrecipitation in CZ-silicon during post-growth two-stage heat treatment has been examined using the methods of high resolution analytical electron microscopy. Electron transparent specimens prepared from these specimens, exhibited a low density of plate type precipitates on {100} planes. Microdiffraction experiments showed the precipitates to be consistently non-crystalline. Electron energy loss spectra showed that the precipitates contained oxygen, but carbon was not detected. It was found that carbon artifact absorption edges could be induced in spectra by specimen contamination in the microscope. The use of a low temperature stage eliminated this problem. Complementary characteristic x-ray microanalysis showed that metallic impurities had not segregated to these precipitates in this particular case, although this has been observed elsewhere.