The semiconductor SiC is a polar compound. As a consequence the opposite faces of {00.1} wafers have different chemical properties and hence different etch patterns. These differences, however, give no convincing evidence as to which side is the Si side and which is the C side of a SiC single crystal. Theoretically, small differences in x-ray reflection intensities are shown to be expected from opposite crystal faces. By careful crystal surface preparation these differences could experimentally be verified. Thus the proper correlation between the Si or C face and the etch patterns has been established.

No abstract

The following paper describes a device in order to separate the inelastically scattered electrons from the electron diffraction pattern. By means of an electric and magnetic deflecting system the diffraction pattern is swept across the small entrance aperture of a filter lens. In this way an electron beam with a small divergence passes the filter lens. Behind the filter lens the electron beam is deflected by another deflection system, which is synchronised with the first. So one gets a diffraction pattern, the angular width of which is determined by the maximum deflection angle of the deflecting system. If the retarding potential of the filter lens is high enough, one can photograph the filtered electron diffraction pattern. By reducing the retarding potential one gets unfiltered diagrams.

No abstract

High energy C+ implantation is used to construct a two crystal monolithic X-ray interferometer. The X-ray interferometer technique is applied to in-situ studies of radiation damage annealing in the interferometer. Volume changes in the crystal due to the transformation of single crystal silicon to amorphous silicon and due to the formation of silicon carbide are measured.