(Invited) Self-Assembly of Aligned One Dimensional ZnO Nanorod Arrays on Electron Beam Lithographically Patterned Templates for Sensor Applications

We have demonstrated the attachment of aligned ZnO nanorod arrays on to the electron beam lithographically patterned oxide surface at lower beam energy. At higher beam energy (similar to 20 keV), the accumulated negative charges that already built on the surface in due course of irradiation restricts the growth of nanorod arrays. This causes a negative shielding potential close to the surface at micron level, and completely unfavorable for the attachment of the negative ZnO carriers. However, at comparatively lower beam energy (similar to 5 keV or less), the secondary electrons are responsible for the pattern with the irradiation zone centered by the local positive field. This allows negatively charged ZnO nanorod arrays to grow at lower beam voltages, which initiate site selective attachments. This protocol of site selection is very useful for various sensor fabrications.