Study on Precipitates in Oxygen-Doped Silicon Single Crystals by X-Ray Diffraction Micrography

The effects of heat-treatments on oxygen-doped silicon single crystals were studied by X-ray diffraction micrography using extinction contrast. For silicon crystals of 1×1018 atoms/cm3 oxygen-concentration, characteristic intensity increase were observed after heat-treatment at 1000°C for several hours, and individual images were resolved after heat-treatment at 1200°C for a few fours. From variation in the shape of images with diffracting planes, it was concluded that the images were due to the disc-shaped precipitates of silicon oxide parallel to {111} planes.