Thomas Wich

Microrobot System for Automatic Nanohandling Inside a Scanning Electron Microscope

In this paper, current research work on the development of an automated nano handling station in a scanning electron microscope (SEM) is presented. An experimental setup is described, in which two mobile microrobots cooperate in the vacuum chamber of an SEM. The robots are positioned by a closed-loop controller with sensor data, which is provided by three charge-coupled device cameras and the SEM. Continuous pose estimation is carried out by processing noisy SEM images in real time. To enable the automation of complex tasks, a client-server control system that can integrate various microrobots and sensors is introduced. Finally, the overall system is evaluated by automatic handling of transmission electron microscope lamellae.

Microrobot system for automatic nanohandling inside a scanning electron microscope

In this paper, current research work on the development of an automated nano handling station in a scanning electron microscope (SEM) is presented. An experimental setup is described, in which two mobile microrobots cooperate in the vacuum chamber of an SEM. The robots are positioned by a closed-loop controller with sensor data, which is provided by three charge-coupled device cameras and the SEM. Continuous pose estimation is carried out by processing noisy SEM images in real time. To enable the automation of complex tasks, a client-server control system that can integrate various microrobots and sensors is introduced. Finally, the overall system is evaluated by automatic handling of transmission electron microscope lamellae.

Assembly inside a Scanning Electron Microscope using Electron Beam induced Deposition

In this paper a new assembly process inside a scanning electron microscope (SEM) is demonstrated. The process includes the separation and handling of a silicon nanowire and its bonding to an atomic force microscope (AFM) probe using electron beam induced deposition (EBiD). EBiD is carried out by using the electron beam of the SEM and a flexible mobile microrobot as transporter of the precursor gas. In addition, experiments are presented to investigate mechanical and chemical properties of the bonded nanowire. Real-time object tracking and image processing are used to measure the force applied to the Si-nanowire. In this way, the load and tension stress on the bonds can be calculated. Finally, energy dispersive X-ray (EDX) analysis is applied to the bonds to estimate their chemical composition

Automated Nano-Assembly in the SEM I: Challenges in setting up a warehouse

Abstract This paper describes the implementation of setting up a warehouse for automated nano-assembly, i.e. the automated registration of the parts processed during the automated assembly. Starting with a brief description of the goals of the assembly process, the overall process structure and its challenges with respect to the micro- and nanoscale are explained. The warehouse task is used as an example for describing the task planning, the necessity to minimize the number of subtasks taking further constraints from the experimental setup into account. For controlling such a complex assembly process, an intelligent and flexible control and communication system architecture is necessary, which will be explained in detail. Based on these considerations, the implementation of the warehouse task and its challenges, including the representation of the parts in the control system, object recognition using generalized models and methods for part origin determination will be presented.

Automatic nanohandling station inside a scanning electron microscope

Current research work on the development of automated nanohandling systems in a scanning electron microscope (SEM) is presented. Two experimental set-ups are shown in which nanohandling robots operate in the vacuum chamber of an SEM. A client—server control system that can integrate various microrobots and sensors has been developed and evaluated by automatic handling of TEM (transmission electron microscope) lamellae by two nanorobots. The robots are controlled in a closed-loop way by using images from several CCD (charge coupled device) cameras and from the SEM. Algorithms for real-time processing of noisy SEM images have been implemented and tested. The experiment on automatic handling of TEM lamellae inside an SEM is described. The other set-up contains a nanohandling robot using the probe of an atomic force microscope (AFM) as end-effector. The manipulation of individual multiwall carbon nanotubes (MWNTs) and the characterization of nanofilms by nanoindentation are the applications being investigated. The experimental set-up includes a nanopositioning piezo stage with three degrees of freedom (DoF) and a three-axis nanomanipulator. Piezoresistive AFM probes are applied as end-effectors. In this way the acting forces can be detected, allowing force feedback for the stations control system. First investigations have been carried out by bending MWNTs and calculating their elastic modulus.

Depth-Detection Methods for CNT Manipulation and Characterization in a Scanning Electron Microscope

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.

Micro-nano-integration based on automated serial assembly

Within this paper an approach for micro-nanointegration of MEMS-based devices or smart miniaturised systems is suggested. In order to overcome the limits of conventional, silicon-based MEMS manufacturing techniques, automated serial nano-assembly processes can be applied. The process chain of such a technique and solutions for key issues with respect to automation are presented. This involves both the key processes and the infrastructure for assembly on the nanoscale. As an application example, results from the automated assembly of carbon nanotube (CNT) based devices in the scanning electron microscope (SEM) are provided.

Robot-based Automated Nanohandling

Within the last ten years, the interest of industry and research and development institutes in the handling of micro- and nanometer-sized parts has grown rapidly [1]. Micro- and nanohandling has become a very common task in the industrial field and in research in the course of ongoing miniaturization. Typical applications include the manipulation of biological cells under an optical light microscope, the assembly of small gears for miniaturized gearboxes, the handling of lamellae cut out of a silicon wafer in the semiconductor industry, and the chemical and physical characterization of nanoscale objects. The number of applications for nanohandling and nanoassembly is expected to grow rapidly with the development of nanotechnology. The handling process is the precursor of the assembly process, hence, in this chapter, these expressions are used equally where not explicitly stated.

Nanohandling automation within a scanning electron microscope

In this paper, current research regarding a semi-automated handling station for TEM-lamella is described. The development of this station started with automated handling of microparts as described in many previous publications. However, within this project, we were able to apply current research to an economically important task for the semiconductor industry - TEM-lamella handling. This task consists of automatic tracking of the lamella, picking it up from the silicon wafer and placing it on a TEM-grid.

Approach for the 3D-Alignment in Micro- and Nano-scale Assembly Processes

Most assembly processes on the nano-scale take place in a Scanning Electron Microscope (SEM) for the reason of high magnification range of the microscope itself. Like all microscopes, the SEM delivers visual data just in two dimensions. This is a bottleneck for all assembly processes which require of course information of the parts to join in a third dimension. This paper shows an approach with a dedicated sensor. As an example for an assembly process a carbon nano tube (CNT) is fixed on a sharp metal tip. The sensor used detects contact between these two parts by exciting a bimorph cantilever made from piezoelectric material. It is shown that with this approach the contact is reliably detected. Recent experiments on introducing a new excitation structure show the possibility to add more dimensional testing in the same way as the one dimensional type.