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During nanoindentation measurements of thin films the formation of cracks within the film as well as of pile-up or sink-in around the indent are known to affect significantly the precision of hardness and Young's modulus values. The crack pattern in brittle films and the amount of pile-up/sink-in in ductile films allow, however, also to estimate film fracture toughness and to gain knowledge on the film strain hardening behavior, respectively. The shape of the residual imprint and the extension of cracks at the surface after unloading are therefore often analyzed by atomic force microscopy or scanning electron microscopy (SEM). However, the contact area under load, the moment of crack initiation and the extension of the cracks during the loading/unloading cycle cannot be deduced unambiguously by analyzing only the residual imprint and the load-displacement data. We present a miniaturized own nanoindentation and nanoscratch device for use inside a scanning electron microscope. The indentation axis is operated at an inclined angle with respect to the SEM column. This allows looking at the surface around the indent during indentation. Crack and pile-up formation can be directly observed with sub-micrometer resolution and linked to the simultaneously recorded load-displacement data. In a first part of the paper the design concepts of the device will be discussed. In a second part, two case studies - indentation of nanocomposite TiN/SiN x coatings and indentation and scratching of hard diamond-like carbon (DLC) films - will be presented to demonstrate the potential of SEM-indentation and scratching. In the case of indentation of hard coatings, the formation of cracks during loading as well as during unloading was observed. Some cracking events could be correlated to discontinuities in the load-displacement curve. Scratch experiments revealed at which critical load coating failure occurred.

This paper presents a micro manipulation platform based on several cm3-sized mobile micro robots. The proposed platform consists of a high resolution XY stage with the mobile micro robots on top of it, a camera with a microscopic objective for the local view and a second camera for the overview and tracking of the robots. The concept of such a manipulation platform is discussed and the platform as it has been realized by the authors is described into detail. Two applications of AFM measurements with an onboard AFM-tool and micro manipulation by adhesion, realized with a similar setup, are discussed.

A new type of microrobot is described. Its simple and compact design is believed to be of promise in the microrobotics field. Stepping motion allows speeds up to 4mm/s. Resolution smaller than 10 nm is achievable. Experiments in an open- loop motion demonstrated a repeatability better than 50 mu m on a 10 mm displacement at an average speed of 0.25 mm/s. A position feedback based on a microvision system will be developed in order to achieve a submicron absolute position accuracy.

Scratch experiments have been used in the past to investigate various contact phenomena such as abrasion mechanisms or asperity contacts. Depending on tip geometries, loading conditions and materials investigated, different crack propagation modes (radial or lateral cracks, etc.) or deformation modes (ploughing, chipping, etc.) may dominate the scratching process. The residual scratch path can yield some information about dominant deformation and fracture modes. It is, however, often not possible to uniquely correlate cracks and other phenomena with events on the recorded load-displacement curves. We have built a miniaturized microscratch device for use inside a scanning electron microscope (SEM) that allows the observation of the surface around the tip with sub-micrometer resolution during scratching. Using a conical indenter with spherical tip we demonstrate on different materials that the device is a powerful tool to observe initiation and propagation of cracks, to observe the flow of the material near the indenter (piling-up and sinking-in) and to study chip and particle formation mechanisms during microscratching. In GaAs, particles were observed to form in front and on the rear side of the tip via interaction of chevron cracks. In the case of a Fe-based bulk metallic glass, shear bands were observed to form in front of the tip leading to serrated chip formation. Discontinuities in the tip penetration during scratching of a polymer thin film were related to the onset of crack formation behind the tip and to the propagation of semi-circular cracks in front of the tip. The observed large elastic recovery of the polymer film at the rear side of the tip has to be taken into account for accurate contact area calculations.

This paper presents a microrobot concept for microhandling and micromanipulation, which has been developed within the framework of the EU founded project MiCRoN. The concept is explained along with some examples of realized modules for the robots and a number of experimental results. The approach for the design of an individual robot is modular, with each module fulfilling a certain function. An overview is given on the system and robot concept, followed by a presentation of several modules for locomotion and tools. The tool modules include microgrippers as well as small scan stages for scanning probes based on piezoelectric monomorph elements. The overall size of the robots is projected to be about 1cm3. Each robot is individually configurable, which means that it can carry e.g. either a gripper, a scanner or other tools. A number of experiments with the robots have been carried out. Promising results were obtained with a number of already existing modules, showing the possibility to use a number of the presented robots for certain micromanipulation tasks, either individually or in cooperation with multiple agents.

We propose a new type of “hybrid” ultrasonic driving principle for our monolithic piezoelectric actuators, which consist of simple electrode patterning on a PZT ceramic substrate The operating principle of the proposed USM is based on the conversion of elliptical motion generated at the leg tip of the actuator into a rigid motion of the slider. The lateral and transversal modes are activated using two sinus signals with a phase shift of 90 degrees. Speed as high as 20mm/s was achieved (with an excitation of 30 kHz) while a resolution as small as 4nm is feasible.

In this paper we present our latest developments in high precision positioning and handling systems operating inside an SEM. The Laboratory in Scanning Electron Microscope concept (LAB-in-SEM) is proposed along with a description of our piezodriven manipulators. Nano-material testing such as in-situ indentation and scratch have been conduct with our systems and are briefly related here. Finally, the preliminary tests of the tele-operated assembly of carbon nanotubes on AFM tips are described.These results will permit the development of an automatic nanotubes assembly system.

The objective of this paper is to present the fundamental phenomena occurring during the scribing and subsequent fracturing process usually performed when preparing surfaces of brittle semiconductors. In the first part, an overview of nano-scratching experiments of different semiconductor surfaces (InP, Si and GaAs) is given. It is shown how phase transformation can occur in Si under a diamond tip, how single dislocations can be induced in InP wafers and how higher scratching load of GaAs wafer leads to the apparition of a crack network below the surface. A nano-scratching device, inside a scanning electron microscope (SEM), has been used to observe how spalling (crack and detachment of chips) and/or ductile formation of chips may happen at the semiconductor surface. In the second part cleavage experiments are described. The breaking load of thin GaAs (100) wafers is directly related to the presence of initial sharp cracks induced by scratching. By performing finite element modelling (FEM) of samples under specific loading conditions, it is found that the depth of the median crack below the scratch determines quantitatively the onset of crack propagation. By carefully controlling the position and measuring the force during the cleavage, it is demonstrated that crack propagation through a wafer can be controlled. Besides, the influence of the loading configuration on crack propagation and on the cleaved surface quality is explained. © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Uniaxial quasi-static tensile testing on individual nanocrystalline Co nanowires (NWs), synthesized by electrochemical deposition process (EDP) in porous templates, was performed inside a scanning electron microscope (SEM) using a microfabricated tensile stage consisting of a comb drive actuator and a clamped–clamped beam force sensor. A 'three-beam structure' was fabricated by focused ion beam induced deposition (FIBID) on the stage, from which the specimen elongation and the tensile force could be measured simultaneously from SEM images at high magnification. A novel strategy of modifying device topography, e.g. in the form of trenches and pillars, was proposed to facilitate in situ SEM pick-and-place nanomanipulation, which could achieve a high yield of about 80% and reduce the difficulties in specimen preparation for tensile testing at the nanoscale. The measured apparent Young's modulus (75.3 ± 14.6) GPa and tensile strength (1.6 ± 0.4) GPa are significantly lower than the bulk modulus and the theoretical strength of monocrystalline samples, respectively. This result is important for designing Co NW-based devices. The origins of these distinctions are discussed in terms of the stiffnesses of the soldering portions, specimen misalignment, microstructure of the NWs and the experimental measurement uncertainty.

For the development of high precision mobile microrobots with a size of about one cm3, capable of micromanipulation tasks, small and precise actuators have to be developed in order to provide the microrobot and its manipulation tools with the required degrees of freedom. The main requirements for these actuators are to be small and precise. In this paper we propose two variants of a high precision miniature rotary microactuator which are developed to fit into a cm3-sized mobile microrobot. These rotary microactuators are driven by piezoelectric actuators and are based on the inertial drive principle. The first version has the advantage to have a thickness of 0.5 millimetres and an outside diameter of 8mm (without the output arm) while the other one is easier to fabricate and to mount on the robot while being a bit wider (1.4 mm). The design, the working principle and some measurement results of those actuators are presented. A version with an integrated gripper is also presented and the integration on a mobile microrobot is discussed.