Bridging the nanogap electrodes with gold nanoparticles using dielectrophoresis technique

We report the assembling of 20 nm gold nanoparticles into the nanogap electrodes by dielectrophoresis (DEP) technique. DEP was performed on electrodes with different gap size values. While the frequency and the applied peak to peak voltage were maintained at 1 MHz and 3 V, respectively, DEP time was varied in accordance with electrodes gap size. Interestingly, some novel assembling was observed during the dielectrophoresis process and the nanogaps were bridged by nanoparticles either forming ring shaped bridges or linear bridges. The assembling of nanoparticles in different form is attributed to the positive DEP effect. This effect is seen to be influenced significantly by the time parameter during which DEP was performed. Results show the promise of dielectrophoresis in controlled engineering of nanoparticles assembly.