Atomic microscope

An atomic microscope or scanning tunneling microscope is, according to Wikipedia, is a powerful instrument for imaging surfaces at the atomic level. The STM can be used not only in ultra high vacuum but also in air, water, and various other liquid or gas ambients, and at temperatures ranging from near zero kelvin to a few hundred degrees Celsius. The STM is based on the concept of quantum tunneling. When a conducting tip is brought very near to the surface to be examined, a bias (voltage difference) applied between the two can allow electrons to tunnel through the vacuum between them. The resulting tunneling current is a function of tip position, applied voltage, and the local density of states of the sample. Information is acquired by monitoring the current as the tip's position scans across the surface, and is usually displayed in image form.

Basic parts needed for an STM include:


 * a computer
 * a digital-to-analog interface
 * analog-to-high-voltage analog amplifiers
 * piezo tube (are there any other alternatives for atomic-resolution positioning?)
 * piezo disk, modified to independently control 4 sectors:, , , , and , , etc.
 * mounting hardware
 * vibration isolation hardware (cases, rubber feet, bungee cords, etc.)
 * tips (there seem to be a wide variety of prices)

Plans

 * Engin Ipek and Sunarni Maulan have posted schematics, source code, etc. for their 2002 scanning tunneling microscope project (via "PC-controlled scanning tunneling microscope using ATMega163").
 * Juergen Mueller provides detailed plans and schematics (PDF) on his website.
 * The University of Münster's Physics Group provideds detailed construction plans and schematics (Eagle)
 * A Swiss high school STM project. Provides overview, processes and basic schematics (PDF).
 * A low-cost (+/- $100) STM project. Good focus on the mechanical portions of the STM, but also with basic schematics (PDF).
 * An amateur STM. Provides homebrew software.
 * Nava Whiteford. "Teeny tiny very small - atomic resolution and the home hobbyist".

Software

 * Gwyddion is a modular program for SPM (scanning probe microscopy, of which STM is a subset) data visualization and analysis and is primarily intended for analysis of height fields obtained by means of SPM techniques (such as STM). FOSS/GPL.


 * GXSM - the Gnome X Scanning Microscopy project. The GXSM software is a powerful graphical interface for any kind of 2D and up to 4D (timed and multilayered 2D mode) data acquisition methods, but especially designed for SPM. It includes methods for 2D data (of various types: byte, short, long, double) visualization and manipulation. FOSS/GPL


 * SPIP - Scanning Probe Image Processor software package for nano- and microscale image processing. Supports multiple formats including STM instrumentation. Commercial/free trial.