Characteristic radiation damages (rod‐like defects) are generated under irradiation of Si and Ge in a HVEM at elevated temperatures (400 to 700°C). The microstructures of the defects extended in 〈110〉 direction can be analysed in their cross‐section in (110)‐oriented samples in a HREM. The electron microscopical images show that in most of the cases the defects lie on {001} and {113} planes, and the displacement vector of {001} defects amounts to R ≈︁ 0.25a〈001〉 and for {113} defects it is R ≈︁ 0.25a〈116〉. The atomic configurations of the defects are compared with various structure models.

Two modifications of double crystal X‐ray topography are applied to detect microdefects in FZ silicon. With about 30 different crystals no contrasts from swirl defects are obtained. However, all the crystals contain defects not reported hitherto. Their dimensions are probably between (or below) 10 and 30 μm and their average density is 103 to 104 cm−3. According to preliminary TEM observations these are presumedly formed by precipitation colonies of an unknown phase. The size of the individual particles is ≦ 200 Å. X‐ray contrast seems to arise only if the defects are located not more than a pendellösung distance from entrance or exit surface. Earlier observations on X‐ray topographic contrast of swirls are discussed on the basis of these results.

The possibilities are investigated of the dark‐field lattice imaging method for observing single point defects. The contrast of single point defects is shown to be sufficiently high to be observed. The value of contrast is mainly determined by the electrical characteristics of single point defects. The intensity distribution in the dark‐field lattice image is strongly connected with the crystal structure projection for a crystal thickness below 10 nm. Positions of intensity maxima coincide with those of double Si atom columns in the (110) projection. Two types of contrast features may be observed by using this technique both, in gold doped Si crystals and in Si irradiated by high‐energy electrons. Abnormally bright and dark contrast in the image may be attributed to Au+ or Si+ split interstitials and vacancies V–, respectively. The presence of vacancies in Au‐doped Si shows that gold diffusion in silicon is controlled by the Frank‐Turnbull mechanism.

Neutron induced defect clusters in silicon are considered. The calculation is based on a model analogous to the radiation damages by Si+‐ion implantation in Si. The results are compared with high resolution TEM‐investigations. The experimental studies in principle confirm these calculations.

I n dislocation-free floating-zone silicon crystals two types of microdefects were observed and analyzed by means of optical and electron-microscopical methods. Microdefects of type I occur in swirl-type arrangements throughout the whole wafer and appear as etch hillocks below which one can find second phase particles. Due t o the chemical-iriechanical polishing near the wafer surface microdefects of type I1 are generated which also occiir in spiral arrangements. These defects could be identified t o be plate-like vacancy agglomerates on { l l l } planes.In versetzungsfrcien zonengeschniolzenen Siliziiiri\liristallen wurden zwei Arten von Mikrodefekten beobachtet nnd niit Hilfe optischer und elektronerimikl.oskopischer Methoden analysiert. Mikrodefekte des Typs I treten in swiilartigcn Ariordnungen tlurch die ganze Scheibe hinclurch auf und erscheinen als Atzhiigel, unter drnen man Teilchen einer zweiten Phase finden lrann. Infolge des cheinisch-mechanischen Poliercns wrrden nahe der Scheibenoberfliiche Mikrodefekte des Typs I1 gebildet, die in spiralforinigen Anordnungen auftreten. Diese Defekte konnten als pllttchenformige Lerrstellenttgglomcrate auf { 111)-Flachen itlcntifiziert werden.