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Current research work on the development of different depth-detection methods for supporting pick-and-place manipulations of carbon nanotubes (CNTs) in a scanning electron microscope (SEM) is presented. A nanorobot station capable of performing this manipulation task in the SEM’s vacuum chamber has been developed, consisting of two cooperating nanorobots. One robot carries an electrothermal microgripper and also performs the coarse approach between microgripper and CNT. The second robot serves as sample holder and realizes the fine positioning of the CNT sample. For a reliable fine approach between microgripper and CNT as well as an intended future automation of handling tasks, depth-detection methods are required in order to precisely measure and align the z-position of microgripper and CNT. Two different methods for z-position estimation are proposed. The depth from focus method uses the focusing information of SEM images whereas the touchdown sensor concept relies on a bimorph piezo bending actuator. The feasibility of both approaches is shown and first experimental results are discussed. Future work has to show how the proposed methods will increase the efficiency of nanorobotic manipulation and how these methods can advance the automation of nanohandling tasks.

Current research work on the development of a nanorobot station for the manipulation and characterization of carbon nanotubes is presented. Therefore two nanorobots are cooperating in the vacuum chamber of a scanning electron microscope (SEM). One robot is carrying a nanogripper and is used for the coarse positioning. The second robot serves as sample holder and realizes the fine positioning. In the course of automatic handling tasks, depth-detection within the SEM is required. Two different methods for the z-position estimation of gripper and carbon nanotube are proposed. On the one hand a depth from focus method using real-time processing of noisy SEM images and on the other hand a touchdown sensor concept based on a bimorph piezo bending actuator. Both methods are described in a theoretical framework and are partly verified by experimental tests.

Functional devices can be directly assembled using microgrippers with an in situ electron microscope. Two simple and compact silicon microgripper designs are investigated here. These are operated by electrothermal actuation, and are used to transfer a catalytically grown multi-walled carbon nanofibre from a fixed position on a substrate to the tip of an atomic force microscope cantilever, inside a scanning electron microscope. Scanning of high aspect ratio trenches using the nanofibre supertip shows a significantly better performance than that with standard pyramidal silicon tips. Based on manipulation experiments as well as a simple analysis, we show that shear pulling (lateral movement of the gripper) is far more effective than tensile pulling (vertical movement of gripper) for the mechanical removal of carbon nanotubes from a substrate.

Amorphous silicon rich silicon nitride optical waveguides clad in silica are presented as a high-index contrast platform for high-density integrated optics. Performance of different cross-sectional geometries have been measured and are presented with regards to bending loss and insertion loss. A sample double ring add-drop filter is presented.

The optical nonlinearities of amorphous silicon rich nitride corresponding to χ(3) in a static electric field have been measured by tracking wavelength shifts in the resonances of optical waveguide ring resonators as a function of an applied electrical field. The magnitude of the nonlinearity measured agrees well with expected values.