Highly patterned growth of SnO2 nanowires using a sub-atmospheric vapor–liquid–solid deposition.

We report the realization of tin-oxide nanowires on patterned structures using a vapor–liquid–solid (VLS) process. While gold acts as the catalyst for the growth of wires, a tin-oxide containing sol–gel solution is spin coated on silicon substrate to act as the source for SnO vapor. The growth of tin-oxide nano-structures occurs mostly at the vicinity of the pre-deposited solution. By patterning the gold as the catalyst material, one is able to observe the growth at desired places. The growth of nanowires is highly dense within 100 µm away from such in situ source and their length is of the order of 5 µm. By further distancing from the source, the growth becomes more limited and nanowires become shorter and more sparsely distributed. The growth of nanowires has been studied using scanning and transmission electron microscopy tools while their composition has been investigated using XRD and EDS analyses. As a novel application, we have employed the grown nanowires as electron detection elements to measure the emitted electrons from electron sources. This configuration can be further used as electron detectors for scanning electron microscopes. [ABSTRACT FROM AUTHOR]