DIELECTROPHORETIC ARCHITECTURES - Bio-Inspired and Nanoscale Integrated Computing - page 165

Figure 5.9. Microscope images of 4-electrode parallel reconfiguration of nano-
wires. Each pair of diagonally opposite electrodes is held at a constant
relative phase of 180

, while the relative phase between the upper-left and
upper-right electrodes is modulated from (a) 0

1

1 to (b) 180 1 to (c) 0 1 .Scalebarsare

20 mm.

where F drag is the drag force per unit length, r wire is the nanowire density, u is the
nanowire velocity, and Re d r solv u m is the Reynolds number for solvent density

r solv and dynamic viscosity m . Assuming bulk mechanical properties of silicon and
benzyl alcohol [23] and matching drag and dielectrophoretic forces, the terminal
velocity during switching perpendicular to the nanowire axis is calculated to be
u > E

=

30 m m/s, implying a 0.3-s reconfiguration time. This time is consistent with
the serial reconfigurations observed, validating our model.

5.3.4. Disassembling Nanowire Interconnects
Finally, it should be mentioned that electrically driven nanowire disassembly was
also found to occur. In an example of this effect, a single nanowire that was
initially trapped on one electrode, as shown in Figure 5.10a, was pulled into the
inter-electrode region and a gas bubble immediately formed there, as shown in
Figure 5.10b. After the bubble dispersed, only short nanowire fragments
remained, as shown in Figure 5.10c. This effect was observed for about 1/3 of