51 research outputs found

    Fiber-top cantilevers: a new sensor on the tip of a fiber

    Get PDF
    Micromachined cantilevers are the most elementary example of miniaturized sensors. A free-standing rectangular beam can often detect changes in the chemical, biological and physical properties of the surroundings with sensitivity comparable to much more complicated devices. It is therefore not surprising that this simple design is still at the heart of several scientific instruments

    Multifunctional Tool for Expanding AFM-Based Applications

    Get PDF
    A multifunctional tool which expands the application field of atomic force microscope-based surface modification is presented. The AFM-probe can be used for surface modification and in-situ characterization at the same time, due to a special configuration with two cantilevers. Various applications from different fields are presented, which were carried out with one and the same tool: in-situ characterization of wear generated with and without local lubrication (tribology), fountain-pen lithography in which material is deposited or removed (physical chemistry), and electrochemical metal deposition (electrochemistry)

    Three dimensional adhesion model for arbitrary rough surfaces

    Get PDF
    We present a 3D adhesion model based on the JKR theory applied locally for all contacting asperity couple and the calculations account the van der Waals interaction beside the externally applied force. Thus, equilibrium of the system is determined by an extremum in the free total energy and subsequently the contact and the adhesion parameters are computed for that particular position. The model estimates the adhesion of contacting arbitrary rough surfaces taking into account that asperities deform according to one of the three deformation regimes (elastic, elasto-plastic and plastic). The deformation of the contacting asperities is determined by the material properties, the asperity characteristics as well as the surface topography. Results show that even outside the bonding regime the specific bonding energy is still high enough to cause adhesive problems for microstructures

    Fiber-top atomic force microscope

    Get PDF
    We present the implementation of an atomic force microscope (AFM) based on fiber-top design. Our results demonstrate that the performances of fiber-top AFMs in contact mode are comparable to those of similar commercially available instruments. Our device thus represents an interesting\ud alternative to existing AFMs, particularly for applications outside specialized research laboratories, where a compact, user-friendly, and versatile tool might often be preferred

    Fiber-top cantilever:a new generation of micromachined sensors for multipurpose applications

    Get PDF
    Fiber-top cantilevers are new monolithic devices obtained by carving a cantilever out of the edge of a single-mode optical fiber. Here we report evidences of their potential impact as sensing devices for multipurpose applications

    Distinction of the irreversible and reversible actuation regions of B-doped poly-Si based elctrothermal actuators

    Get PDF
    Polycrystalline-Si microactuators based on electrothermal principles exhibit many interesting features but their practical use is severely limited by permanent damage that may occur due to accidental overheating. Under these conditions, polycrystalline-Si structures will display irreversible structural changes ranging from slight geometrical deformations to complete damage. In this paper, an approach is presented to avoid permanent structural deformation of B-doped polycrystalline-Si based electrothermal actuators by overheating. The method allows us to distinguish reversible and irreversible actuation conditions and is demonstrated under environmental and vacuum conditions. It enables full utilization of the capabilities of B-doped polycrystalline-Si based electrothermal actuators with reproducible performance
    corecore