Structured Polymer Brushes on Silicon Carbide

A straightforward method is presented for the preparation of homogeneous as well as structured polymer brushes on SiC substrates. The self-initiated photografting and photopolymerization (SIPGP) of styrene and N,N-dimethylaminoethyl methacrylate (MAEMA) allows the preparation of polymer brush layers directly and selectively onto C-OH terminated (000 (1) over bar) 6H-SiC surfaces in a single step reaction. In contrast, the analogous reaction oil Si-OH terminated (0001) 6H-SiC does not occur. The reactivity contrast between Si-OH and C-OH terminated crystal faces for SIPGP was studied using the density functional theory method which showed it higher SiO-H bond dissociation energy for hydrogen abstraction oil the Si-polar relative to the C-polar crystal face. Furthermore, structured polymer brushes Oil the submicrometer scale could be prepared by the carbon templating (CT) technique on Si-OH terminated (0001) 6H-SiC surfaces. First,ail ultrathin template layer was formed by electron beam induced carbon deposition (EBCD) on SiC by means of a focused electron beam. Amplification of the template by SIPGP resulted in polymer brush structures with controlled three-dimensional shapes. The effect of the applied electron dose as well as the initial lateral structure size oil the brush layer morphology was investigated.