By Cameron Chai
Researchers belonging to the University of Limoges in France have demonstrated the possibility of creating three-dimensional silicon oxide nanodots on silicon films at the micrometric scale, within a few seconds. The nanodots are highly reproductive.
Xavier Landreau, along with his partners at the university demonstrated the novel method. The study is to be published in the European Physical Journal D (EPJD) for Atomic, Molecular, Optical and Plasma Physics. The researchers managed to develop a square array of nanodots that have potential for biosensor applications in bio-diagnostics and genomics. The nanodots are actually nanoindents that are spaced regularly on the deposition layer.
The researchers employed the atmospheric pressure plasma-enhanced chemical vapour deposition method, which is a quicker alternative to nanoscale lithography and other similar methods, which allow deposition of only a single nanodot at any particular instance. The novel deposition method can be performed at atmospheric pressure, which is an added advantage as it reduces cost when compared to other low-pressure deposition processes.
Other processes for silicon oxide growth do not have the capability to order the nanodots to form an array. The researchers varied the interspacing between the indents so as to emulate the normal distance that the silicon oxide particles travel for getting deposited.
They utilized atomic force microscopy and found that optimum self-ordering occurs within the indents when they adopted silicon substrate temperature and indent spacing. The scientists aimed to comprehend the mechanisms for self-organization that lead to the preferential nanodot deposition in the indents.
Further research will investigate the potential of such nanoarrays for nanosensor applications. Development of the nano arrays on metallic substrates will provide improved control of the driving forces that cause the self-organization of nanodots. Associating individual nanodots with probe molecules that are designed for identifying target molecules will give them sensing ability.