Negative resist material based on polysilanes for electron beam and X-ray lithographies

In the present paper, we describe the mechanisms of photo- and radiation-in duced reactions in silicon based resist materials, polysilanes with Si-bran chings and Si-H bondings, candidates for future resist materials. Polysilan es have been previously confirmed to show positive-type resist properties f or ultra violet (UV) light, electron beams (EB), and X-rays under all condi tions. However, the cross-linking reaction of the polymer became dominant i n the polysilane with Si-branchings, upon irradiation with UV light, EB, an d ion beams. The efficiency of the cross-linking reaction strongly depended on the ratio of Si-branching producing polymer gels in the polysilane with a higher amount of Si-branching than 5%, even with gamma-ray irradiation. Polyhydrosilanes containing vinyl groups were revealed to cause efficient c ross-linking reactions in the presence of catalysts for hydrosilylation upo n exposure to deep UV or X-rays, leading to high-sensitive negative resist materials for extreme UV lithography.