The creation of geometrically well-defined submicron structures on insulating substrates by e-beam lithography is hampered by surface charging. This problem becomes crucial when trying to create nanosized protein patterns by selective molecular assembly patterning (SMAP) on transparent glass substrates. In this paper we demonstrate that the use of thin films of conductive indium tin oxide resolves the issue of surface charging during e-beam writing while being compatible with the standard SMAP protocol for surface modification.

Electron beam lithography patterning of sub-10 nm line using hydrogen silsesquioxane for nanoscale device applications J. Vac. Sci. Technol. B 23, 3120 (2005); 10.1116/1.2132328 Fabrication of identical sub-100 nm closely spaced parallel lines using electron beam lithography Nanoscale device isolation of organic transistors via electron-beam lithography Appl. Phys. Lett. 86, 033113 (2005); 10.1063/1.1854217Resist debris formation and proximity exposure effect in electron beam lithography A high-resolution negative Calixarene resist has been used to pattern 2-nm-thick TiO 2 films on 50-nm-thick Pt layers by electron beam lithography, in order to carry out site controlled growth of Pb͑Zr, Ti͒O 3 structures. Single dot structures have been written in a 60-nm-thick Calixarene layer at e-beam acceleration voltages of 10 kV ͑100 pA͒ and 20 kV ͑200 pA͒. The necessary dose for complete dot development ranged from 5 to 25 mC/ cm 2 . Due to the high density Pt layer, the dot-size depended very much on the volume of backscattered electrons. The minimum dot size ͑70 nm͒ was found to lie in the range of the resist film thickness. Proximity effects have been studied. At smaller beam energies, a reversed proximity effect has been observed, in the sense that the dot size decreased due to proximity. An irradiation model is proposed based on exposure from bottom to top, and taking into account a competition between cross-linking and bond-scission.