| Simple, safe and cost effective one dimensional nanostructure growth system was designed towards direct fabrication of nanostructure device array. By controlling growth parameters such as temperature, time, gases, and stacking order of catalyst and supporting layer in electrodes, various array structures with carbon nanotubes and nanowires were directly fabricated without pre or post process. Stacking order and growth temperature play significant roles in fabrication of nanostructure arrays. Especially, titanium layer plays critical roles in both carbon nanotube and silicon nanowire growth acting as diffusion barrier, adhesion layer, catalyst diffusion membrane and promoting layer for silicides formation.; Miniaturization of device structures was accomplished with carbon nanotube and silicon nanowire by direct fabrication. Carbon nanotube field emission gas sensor shows significant sensitivity and selectivity on polar gas 147 molecule in the presence of electric field during exposure. Tunneling liquid molecule sensor shows very sensitive response and selectivity on species of liquid molecules. Unique concept of nanowire electro-mechanical switch was fabricated by direct growth of nanowires from electrodes. Switching characteristic shows linear behavior with the amplitude of back gate bias. |
