Radiation polysilane effects

Ionizing radiation. Further studies on the effects of ionizing radiation such as 60Co y-ray radiation and ion beams on polysilanes have been reported.295 304-306 Both positive and negative resist properties can be shown, depending on the side-chain type, branch density, and the presence or absence of radical initiators. 

We have found that a certain number of polyhalogenated aromatic derivatives such as compounds 1-3 greatly accelerate the rate of bleaching of a number of poly silane derivatives in the solid state (33). This effect is dramatically demonstrated in Figure 5 for a PM PS film doped with —20% by weight of l,4-bis(trichloromethyl)benzene, 1. Similar results were obtained with substituted triazine sensitizers such as 2. In these cases, the polysilane is the primary absorber of the incident radiation. Interestingly, when compound 3, which absorbs at —400 nm, was incorporated into a PM PS film and the sample was irradiated at 404 nm, where only the sen-... 

Within these main categories a number of subdivisions will generally be found, usually based on the nature of the groups attached to silicon. The emphasis in the subject matter is chiefly in terms of the chemical transformations effected by the radiation, and little emphasis is placed on the photochemical mechanisms involved, which are dealt with in an accompanying chapter of this treatise. Also, the photochemistry of high molecnlar weight polysilane polymers, or of polymers containing silicon as part of the backbone of the molecules, is not dealt with in this chapter, but some relevant material will be found in other chapters in this volume. 

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