Polyferrocenylsilanes as Reactive Ion Etch Resists

Filially, magnetic force microscopy (MFM) indicated no appreciable magnetic field gradient above the bars after EBL. 

Although the aforementioned proof-of-concept experiments dealt with the formation of micron-scale objects, EBL can be used to routinely fabricate structures down to 30-50nm. Indeed, this process has already been extended to the patterning of sub-500-nm bars and dots from Co-PFS. 

It has been demonstrated that polyferrocenylsilanes possess low plasma etch rates, which can be attributed to the formation of a protective layer of involatile iron and silicon compounds. This property has been exploited with PFS block copolymers self-assembled into micelles or phase-separated thin films to deposit patterned ceramics as well as for pattern transfer to the substrate. In our research, we are interested in the direct formation of high metal content magnetic ceramic films by RIE treatment of Co-PFS in the presence of a secondary magnetic field.  

Morphological changes in the surface of Co-PFS films after RIE were investigated by TEM and AFM. Thin films of the polymer (ca. 50 nm thick) on a carbon-coated copper TEM grid were exposed to oxygen and hydrogen plasma. In both cases, analysis by TEM revealed the presence of electron-rich nanoworms with 

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