Tepelná stabilita plasmaticky deponovaných polysilanů

Abstract

Nová metoda pro studium termické stability a chemických změn při ohřevu polymerních filmů. Byla aplikována na termaální a vlastnosti a strukturu tenkých polymerních filmů, připravených radio frequency plasma enhanced chemical vapour deposition (RF PE CVD). Struktura byla zkoumána fluorimetrií, FTIR absorbční spektroskopií a XPS. Bylo zjištěno, že plasmatické procesy degradují ve třech následných krocích. Nanostrukturální jednotky nízkodimenzionálních polysilanů umožňují pokrýt luminiscenci ve spektrální oblasti od UV (360 nm) po řervenou (600 nm).

A new method for studying thermal stability and concomitant chemical composition changes on thermal treatment of thin polymeric films is presented. It is applied to the study of thermal properties and modification of properties of polysilane-like materials with variable dimensionality prepared by radio frequency plasma enhanced chemical vapour deposition (CVD). Structure and microphysical properties of these materials, modified by progressive annealing, are examined by fluorimetry, FTIR absorption spectroscopy and XPS. In addition, the role, bonding conditions and structural environments of organic moieties as well as their influence on thermal degradation processes are examined. It is found that plasma polysilanes undergo three consecutive thermal degradation processes: Si-Si bond cleavage, elimination of side groups and final carbide formation. Presence of disorder and crosslinking stabilises the plasmatic material in comparison to classically prepared polysilanes. Nanostructural units in low dimensional polysilanes enable the peak of the luminescence to be adjusted in the spectral range from near UV (360 nm) to red (600 nm).