polymer brushes using electron beam lithography. All polymer brushes were grown via surface initiated atom transfer radical polymerization (SI-ATRP). Conventionally, high resolution patterning of polymer brushes is done by first producing a patterned initiator layer on the substrate, followed by surface initiated polymerization of a suitable monomer. Techniques such as microcontact printing, two- dimensional gradients, scanning probe microscopy techniques, nano- imprint lithography and chemical lithography have been used to fabricate patterned initiator monolayers. A drawback to growing polymer brushes from a patterned initiator layer is that it can lead to lower resolution features when the brush height is comparable in length to the pattern width due to chain relaxation into the voided regions during growth. Additionally, these approaches involve labor intensive steps, making them unattractive for practical use. The inclusion of multiple steps also increases the chance of surface contamination. It would be highly advantageous to make the patterning procedure a single step process. We have recently studied methacrylic polymers and their use as intrinsic high-resolution positive tone e-beam resists for direct patterning after brush formation. We have demonstrated the successful direct patterning of such brushes and characterized the polymer brush resist behavior.
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