The change in the diffracted intensity of a silicon 400 Bragg peak is measured in situ while the sample is exposed to a thermal treatment up to 1150 °C. The experiments are set up in focusing Laue geometry with polychromatic and divergent x-rays generated by a high voltage tube. Changes in peak intensity and shape are only observed for Czochralski grown samples and not for the float zone grown reference group. Thus, they are attributed to oxygen related defects emerging at these temperatures.

Oxygen precipitation in silicon has been studied in-situ by high energy X-ray diffraction. A gain of diffracted intensity is expected if an ideal crystal is distorted by growing precipitates as the diffraction mode changes from a dynamical to a more kinematical one. Irreversible changes in the intensity of a 220 and a 400 Bragg peak are detected for Czochralski grown samples only, but not in a float zone grown reference crystal. Thus, these changes are attributed to oxygen precipitation, which is confirmed by a subsequent classical ex-situ characterization. Further, the changes of the intensities of the two measured Bragg peaks are compared to each other to get the level of change in the diffraction mode from a dynamical to a kinematical one. The detection limit of the specific setup is estimated via a simulation of the defect inventory to correspond to a precipitate diameter of 50nm with the density of 6.9•109 1/cm3. The diffraction experiments are done with polychromatic and divergent X-rays generated by a laboratory source, albeit with high energy. This results in a simple and accessible setup for the characterization of oxygen precipitates.

A focusing Laue diffractometer is used to analyze the strain field in silicon. The source for this so called strain field diffraction (SFD) setup is a high energy X‐ray tube. In the present work this setup is used to monitor the strain generated by growing oxygen precipitates (Bulk Micro Defects, BMDs) in situ at temperatures up to 1000 °C. By choosing appropriate thermal treatments a correlation of the SFD signal with BMD parameters gained with conventional analytic techniques (FT‐IR, infra red light scattering, TEM) is established. From this, the detection limit of the SFD setup for BMDs is determined at a diameter of 7 nm and a density of 1013 cm−3. This range is only covered by TEM so far. Further, the diffracted intensity provides a measure for the level of precipitation occurred.

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A defocused Laue diffractometer setup operating with the white beam of a high energy X-ray tube has been used for a topographic visualization of structural defects in semiconductor wafers. The laboratory white beam X-ray topograph of a Czochralski Si wafer with oxygen precipitates grown in an annealing process is compared to a μPCD image. Further, the dislocation network in a VGF GaAs wafer is studied under thermal annealing up to 1140°C and the in-situ capability of the setup is demonstrated.