From Pixels To Probes: Demystifying AFM Software

By Beau Brossman and Aedan Gardill, Ph.D., Mad City Labs Inc.

In addition to managing the AFM’s motion control hardware and phase lock loop (PLL) controller, system software must organize the acquired data into an acceptable format for analysis, along with the measurement parameters in some form of metadata. Whether using an off-the-shelf AFM system with control software implemented or programming a custom-built system from the ground up, user understanding of the basic functions of AFM software, as well as how to optimize experiment flexibility and component interoperability using that software, is critical.

Motion control requires a high-resolution positioner and an analog-to-digital converter (ADC) to report the stage’s position to the software. Additionally, the PLL controller and the positioning controller must relay probe and Z-axis data to the software, so it is aware of the probe’s activity, such as whether the probe has touched the sample surface. The PLL controller is the most complex AFM component for software to manage because of the numerous parameters they are capable of controlling.

Moreover, AFM users are constantly finding new approaches to modify experiments or using probe tips in novel ways. Therefore, flexible system control software is as important as adaptable hardware.