Francesc Pérez-Murano

Local oxidation of silicon surfaces by dynamic force microscopy: Nanofabrication and water bridge formation

Local oxidation of silicon surfaces by atomic force microscopy is a very promising lithographic approach at nanometer scale. Here, we study the reproducibility, voltage dependence, and kinetics when the oxidation is performed by dynamic force microscopy modes. It is demonstrated that during the oxidation, tip and sample are separated by a gap of a few nanometers. The existence of a gap increases considerably the effective tip lifetime for performing lithography. A threshold voltage between the tip and the sample must be applied in order to begin the oxidation. The existence of a threshold voltage is attributed to the formation of a water bridge between tip and sample. It is also found that the oxidation kinetics is independent of the force microscopy mode used (contact or noncontact).

Mechanical detection of carbon nanotube resonator vibrations.

Bending-mode vibrations of carbon nanotube resonators were mechanically detected in air at atmospheric pressure by means of a novel scanning force microscopy method. The fundamental and higher order bending eigenmodes were imaged at up to 3.1 GHz with subnanometer resolution in vibration amplitude. The resonance frequency and the eigenmode shape of multiwall nanotubes are consistent with the elastic beam theory for a doubly clamped beam. For single-wall nanotubes, however, resonance frequencies are significantly shifted, which is attributed to fabrication generating, for example, slack. The effect of slack is studied by pulling down the tube with the tip, which drastically reduces the resonance frequency.

Electromechanical model of a resonating nano-cantilever-based sensor for high-resolution and high-sensitivity mass detection

A simple linear electromechanical model for an electrostatically driven resonating cantilever is derived. The model has been developed in order to determine dynamic quantities such as the capacitive current flowing through the cantilever-driver system at the resonance frequency, and it allows us to calculate static magnitudes such as position and voltage of collapse or the voltage versus deflection characteristic. The model is used to demonstrate the theoretical sensitivity on the attogram scale of a mass sensor based on a nanometre-scale cantilever, and to analyse the effect of an extra feedback loop in the control circuit to increase the Q factor.

Predictive model for scanned probe oxidation kinetics

Previous descriptions of scanned probe oxidation kinetics involved implicit assumptions that one-dimensional, steady-state models apply for arbitrary values of applied voltage and pulse duration. These assumptions have led to inconsistent interpretations regarding the fundamental processes that contribute to control of oxide growth rate. We propose a model that includes a temporal crossover of the system from transient to steady-state growth and a spatial crossover from predominantly vertical to coupled lateral growth. The model provides an excellent fit of available experimental data.

STM-Induced Hydrogen Desorption via a Hole Resonance

We report STM-induced desorption of H from

Ultrasensitive mass sensor fully integrated with complementary metal-oxide-semiconductor circuitry

\mathrm{Si}\left(100\right)\ensuremath{-}\mathrm{H}\left(2\ifmmode\times\else\texttimes\fi{}1\right)

Dynamic range enhancement of nonlinear nanomechanical resonant cantilevers for highly sensitive NEMS gas/mass sensor applications

at negative sample bias. The desorption rate exhibits a power-law dependence on current and a maximum desorption rate at

Integrated CMOS-MEMS with on-chip readout electronics for high-frequency applications

\ensuremath{-}7\mathrm{V}

Nanometer-scale oxidation of Si(100) surfaces by tapping mode atomic force microscopy

. The desorption is explained by vibrational heating of H due to inelastic scattering of tunneling holes with the Si-H

Anisotropic growth of long isolated graphene ribbons on the C face of graphite-capped 6H-SiC

5\ensuremath{\sigma}