Spatial organization of ZnO nanorods on surfaces via organic templating

by Hsu, Julia W. P.; Tian, Z. Ryan; Simmons, Neil C.; Matzke, Carolyn M.; Voigt, James A.; Liu, J.

Zinc oxide (ZnO) is a technologically important material because of its multi-functional properties, with applications ranging from piezoelectric transducers and varistors to wide-bandgap semiconductor for UV emitters and detectors. In addition to polycrystalline ceramic powders and epitaxial thin films, recent advances in ZnO have been in vapor and solution phase growth of complex nanostructures. For these nanostructures to be useful, a means to place them strategically on the surface is needed. Here we will describe using micro-contact printing to pattern self-assembled monolayer (SAM) molecules that locally inhibit crystal growth on surfaces. These chemically patterned surfaces are then used as templates for ZnO nanorod growth in aqueous solutions. We demonstrate good control of crystal placement with feature size down to 1 mu m. In addition, we find that restricting active nucleation regions results in a marked increase in nucleation density. These results are the first demonstration of combining soft lithography and bio-inspired crystal growth to make nanostructures of ZnO. The success illustrated here indicates that such a combination may be applicable to a much broader, range of materials systems than previously envisioned.

Proceedings of SPIE
1996-756X; 0277-786X