ATOMS Home STM Basics Imaging Atoms and Surfaces Imaging for Materials Science The easyScan STM System ATOMS in the Classroom Opportunities for Students ATOMS Discussion Forum Register Here for the       Discussion Forum ATOMS Picture Gallery ATOMS Related Links

The easyScan STM System The easyScan STM system produced by the Swiss company NanoSurf AG makes Scanning Tunneling electron Microscopy (STM) accessible in virtually any lab setting. Its small size and ease of use permit STM of metallic (and other conductive) surfaces at atomic resolutions even in high school classrooms. Using this tool Project ATOMS is bringing the world of the nanometer scale to students and teachers in the Southeastern Ohio region. This section of our site will describe the features and outline the operation of the easyScan STM system. Overview Elements of an operational easyScan system include those pictured on the left: a computer with a serial interface, the easyScan control electronics (white box), and the scan head itself mounted on a granite base.     The heart of the system is the easyScan scan head pictured here. During automated sample approach and during scanning it is enclosed in a plastic cover as on the left. The image below shows the scan head and sample bay uncovered.   Notice the cylindrical silver sample carrier at rest in the sample bay.   The easyScan STM automatically positions a sample to be scanned using a piezo-electric positioning motor to move the sample carrier close enough to the fine metal probe tip for a tunneling current to begin flowing between tip and sample. Then it creates an image of a sample's surface using finer x, y, and z axis piezo positioners to scan across and along the sample as illustrated below: Signals from the probe tip are sent to the control electronics and from there to the easyScan software which processes the signals to form an image based on the tip's up and down movement as it scans across the sample surface.   Using the easyScan STM There are three steps to creating images using the easyScan system: Inserting the probe tip. Bringing the sample within tunneling distance of the probe. Using the easyScan software to control the scan and produce images of the desired features at the scale of resolution which one wants to investigate. We will look at each of these steps in turn.