STRUCTURE AND OPTICAL-PROPERTIES OF TERNARY SI-C-H FILMS PREPARED BY EVAPORATION OF ORGANO-POLYSILANE

Ternary Si:C:H films are prepared by evaporating per-methyl-polysilane powder. The structure and optical properties of the films obtained are examined by various techniques. From infrared absorption and x-ray diffraction measurements, it is found that the film prepared at 27-degrees-C contains a Large number of Si backbones with an alternating trans-gauche conformation. The ultraviolet absorption spectrum shows a large peak at 300-350 nm and also supports the existence of one-dimensional Si chains. On the other hand, the film prepared at 300-degrees-C contains a large number of helical backbones and shows a narrow absorption hand at 300 nm. The strength of this absorption band strongly depends on measurement temperature, suggesting excitonic absorption.