A commercial atomic force microscope (AFM), originally designed for operation in ambient conditions, was placed inside a compact aluminum chamber, which can be pumped down to high vacuum levels or filled with a desired gaseous atmosphere, including humidity, up to normal pressure. The design of this environmental AFM is such that minimal intrusion is made to the original setup, which can be restored easily. The performance inside the environmental chamber is similar to the original version.

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We have investigated an experimentally moderate bending of multiwalled carbon nanotubes (MWNTs) in the perpendicular direction from flat substrates. The tubes were in the diameter range of 3–13nm and deposited over lithographically fabricated gold lines whose height determined the total bending. In our model for the bending profile we take into account the van der Waals attraction between the substrate and the MWNT and the opposing elastic bending force. With reasonable parameters for the competing forces we obtain an agreement between the model and the experimental data for the critical distance between two adjacent lines when the van der Waals attraction can no longer prevent elastic forces from straightening the tube to a suspended position between the lines. However, for the smallest nanotubes a simple classical model is clearly insufficient.

Ultrathin layers of polypyrrole (PPy) were electrochemically grown between microelectrodes on a Si/SiO(2) substrate. Conducting nanolayers of PPy are directly grown onto ultrathin discontinuous gold (Au) film between the microelectrodes, with thicknesses in the range 10-100 nm. The system therefore forms a novel (PPy/Au) nanocomposite conductor. Atomic force microscopy (AFM) imaging and conductivity measurements indicate that at all thicknesses a relatively uniform film is formed but with significant roughness that reflects the roughness of the metallic island layer. In PPy/Au films with thickness ∼10 nm, the small barriers around the gold islands dominate the conduction, and as the film thickness increases to 100 nm the intrinsic conductivity of highly doped PPy dominates the charge transport.

We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlO(x) barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an atomic force microscope tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed up to a value of 37. This facilitates local static strain variation measurements down to approximately 10(-7). This type of strain sensor could have applications in nanoelectromechanical systems used in displacement, force, and mass sensing, for example.