We use Monte Carlo simulations and modeling to study the 1/<i>f</i> noise in CNT films as a function of device parameters
and film resistivity. We consider noise sources due to both tube-tube junctions and nanotubes themselves. By
comparing the simulation results with experimental data, we find that the noise generated by tube-tube junctions
dominates the total CNT film 1/<i>f</i> noise. We then systematically study the effect of device length, device width and film
thickness on the 1/<i>f</i> noise scaling in CNT films. Our results show that the noise amplitude depends strongly on device
dimensions and on the film resistivity, following a power-law relationship near the percolation threshold. Despite its
relative simplicity, our computational approach explains the experimentally observed 1/<i>f</i> noise scaling in CNT films.
Since 1/<i>f</i> noise is a more sensitive measure of percolation than resistivity, these simulations will help improve the
performance of CNT film sensors at the micro-nano interface, where noise is an important figure of merit.
We fabricate and experimentally characterize metal-semiconductor-metal (MSM) photodetectors with CNT film
Schottky electrodes on <i>n</i>-type and p-type silicon substrates. We extract a Schottky barrier height of ~0.45 eV and ~0.51
eV for CNT films on <i>n</i>-type and p-type Si respectively. The extracted barrier height corresponds to a CNT film
workfunction of 4.5-4.7 eV, which is within the range of the previously reported workfunction values for individual
CNTs. Furthermore, we find that while at temperatures above 240°K thermionic emission is the dominant transport
mechanism, at lower temperatures tunneling begins to dominate. We also characterize the photoresponse of the CNT
film-Si MSM photodetector by illuminating the samples with a 633 nm HeNe laser. We observe that while the
photocurrent of the CNT film MSM devices is similar to that of the Ti/Au control samples at high biases, their lower
dark current results in a higher photo-to-dark current ratio relative to the control devices. We explain these observations
by comparing the two interfaces. This work opens up the possibility of integrating CNT films as transparent and
conductive Schottky electrodes in conventional semiconductor electronic and optoelectronic devices.
We present the scaling of percolation resistivity in nanotube films as a function of nanotube and device
parameters both experimentally and using simulations. We first characterize the resistivity of these films down to 200
nm lateral dimensions by fabricating standard four-point-probe structures. We find that the film resistivity starts to
increase at device widths below 20 microns, and exhibits an inverse power law dependence on width below a critical
width of 2 microns. We then use quasi-3D Monte Carlo simulations to model and fit these experimental results. In
addition to fitting the experimental data, we also study the effect of four parameters, namely nanotube density, length,
alignment, and measurement direction on resistivity and its scaling with device width. We explain these simulation
results by simple physical and geometrical arguments. Nanoscale study of percolation transport mechanisms in
nanotube films is essential for understanding and characterizing their performance in nanosensing device applications.