Chronology
John Alexander’s STM (2003)
The first STM using a piezo disk.
It uses an external oscilloscope to display the output and an external function generator to control the tip. Because of that, the microscope itself is extremely cheap. But does not have some cool features like adjustable speeds, bias, compensation. It does not have atomic precision.
STM Brasil (2010)
Similar to the one from John Alexander, but even cheaper.
Dan Berard’s STM (2011)
Has atomic resolution. Uses a digital control loop.
Vitor Barbosa’s STM (2021)
Based on the Dan Berard’s STM and Dan Berard’s unfinished AFM.
The STM has atomic resolution, and the AFM doesn’t seem to work.
The circuits are separated in small modules.
It has two versions, A and B. The B version is cheaper and achieves basically the same functionality.
It uses rechargeable lithium batteries to avoid noise from the power supply.
OpenSTM (2023)
Uses a linear slider. Has capacitive sensing to achieve fast coarse approach.
Mechanical Panda’s STM (2023)
3D printed