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Starting from the well-known idea of atomic shadowing during growth (i.e. ballistic aggregation) a computer model is developed which includes surface relaxation by thermally induced surface diffusion, desorption, angular distribution of the oncoming atoms, and atomic attraction as well for one-and two-(or more-) component systems. This enables to consider such deposition parameters as substrate temperature, energy of oncoming particles, deposition geometry, and inert gas pressure. The model is applied to investigate the influence of various deposition parameters on the morphology of thin films, especially on the structure of nodular defects.Ausgehend vom bekannten Ansatz der atomaren Abschattung (d. h. der ballistischen Aggregation) ist ein Rechnermodell fur das Dunnschichtwachstum beim Aufdampfen und Sputtern entwickelt worden, das fur ein-und mehrkomponentige Systeme die thermisch induzierte Oberflachendiffusion, Desorption, die Winkelverteilung der einfallenden Atome und deren Wechselwirkung mit der Schicht einschliel3t. Es erlaubt dadurch, solche Abscheideparameter wie Substrattemperatur, Energie der einfallenden Teilchen, Abscheidegeometrie und Inertgasdruck mit zu berucksichtigen. Das vorgestellte Model1 wird benutzt, um den EinfluB verschiedener Abscheideparameter auf die Schichtmorphologie, insbesondere die Struktur nodularer Defekte zu untersuchen.

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According to the method for solving the non‐linear (time‐dependent) heat transport equation described in Part I of the paper the temporal formation of the filament and by it the corresponding temperature distributions, the temporal behaviour of current and voltage at the device as well as the resulting delay, switching, and recovery times have been calculated numerically for three special parameter constellations. In the formation of the high‐conductivity filament a certain “inertia” appears which leads in general to a dynamic peak in the temporal development of the temperature at the centre of the sample. Further the influence of certain parameters on the switching characteristics of the device has been investigated.

To investigate the dynamic (specially the pulse) behaviour of VO2 coplanar switching devices a phenomenological theory of thermal threshold switching is developed in the framework of an one‐dimensional model. The corresponding non‐linear (time‐dependent) heat transport equation is solved approximately by an iteration procedure. General expressions are derived for the current and the voltage at the device as well as for the temperature distribution within the sample. The general theory will be evaluated numerically for some special cases in PartII of the paper.