Synthesis and Preparation of Ionically Bound Dendrimer Monolayers and Application toward Scanning Probe Lithography

Dendrimer monolayers have been designed for use as positive resists for scanning probe lithography (SPL). Several new amphiphilic poly(benzyl ether) dendrimers with carboxylic acids at either the focal point or the "periphery" have been prepared. These can form ionically bound dendrimer monolayers that may serve as either positive or negative tone resists for SPL. The amphiphilic dendrimers self-assemble onto (3-aminopropyl)silanized Si(100) wafer surfaces to afford ultrathin films. The dendrimer monolayers were characterized by AFM, ellipsometry, and contact angle goniometry. Patterning a singly charged dendrimer monolayer results in the formation of positive tone holes ∼35 nm in width. Similarly, patterning a multiply charged dendrimer monolayer in a direct-write manner with the scanning probe microscope results in the formation of negative tone oxide features ∼80 nm in width.