Selective surface functionalization of silicon nanowires via nanoscale joule heating.
In this letter, we report a novel approach to selectively functionalize the surface of silicon nanowires located on silicon-based substrates. This method is based upon highly localized nanoscale Joule heating along silicon nanowires under an applied electrical bias. Numerical simulation shows that a high-temperature (>800 K) with a large thermal gradient can be achieved by applying an appropriate electrical bias across silicon nanowires. This localized heating effect can be utilized to selectively ablate a protective polymer layer from a region of the chosen silicon nanowire. The exposed surface, with proper postprocessing, becomes available for surface functionalization with chemical linker molecules, such as 3-mercaptopropyltrimethoxysilanes, while the surrounding area is still protected by the chemically inert polymer layer. This approach is successfully demonstrated on silicon nanowire arrays fabricated on SOI wafers and visualized by selective attachment of gold nanoparticles.
Park
Inkyu
I
Berkeley Sensor and Actuator Center (BSAC), University of California, Berkeley, California 94720-1774, USA. inkyu@eecs.berkeley.edu
Li
Zhiyong
Z
Pisano
Albert P
AP
Williams
R Stanley
RS
D003460:Crystallization / Q000379:methods*; D004559:Electric Wiring / Q000295:instrumentation*; D006358:Hot Temperature; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties
D046911:Macromolecular Substances; D012825:Silicon