Struktur elektrolytischer Schichten im Endwachstum* Eine Untersuchung des Zusammenhanges von Oberflächenform und Vorzugsorientierung mit den Methoden der Elektronenbeugung und Elektronenmikroskopie

Abstract

Concerning the final stage of the crystal growth of electrolytic nickel, copper and gold films it can be shown that a certain preferred orientation is always connected with a special characteristic crystal shape at the surface of the electrolytic films. Using electron-microscope replicas it is seen that in the case of (211) and (110) orientation twinned crystals are predominant and probably responsible for the development of the special one-degree-orientation. The twinning can be deduced from the extra reflections found in the reflection electron diffraction diagram. These extra reflections do not belong to an hexagonal phase as reported in the literature. In addition the existence of twins is demonstrated by means of electron-microscope dark-field image and small-area diffraction technique. These techniques also prove the presence of “crystals” with a “five-fold” rotational symmetry explained by a double twinning mechanism. The correlation of preferred orientation and a typical characteristic crystal shape existing in spite of quite different production conditions and different face-centered cubic metals is explained by the assumption of a common growth mechanism for electrolytic deposition and condensation from vapor.