Molecules can drive a nanomechanical cantilever
(related to the work of Fraser Stoddard, Nobel Laureate in Chemistry 2016).

F. Stoddard & P. Weiss groups, ACS Nano 3, 291 (2009).

40 years of Atomic Force Microscopy (AFM), a brief history

Over the past four decades, Atomic Force Microscopy (AFM) has evolved from a novel imaging technique into one of the most powerful and versatile tools in nanoscience and nanotechnology. By enabling the visualization of non-conductive materials with true molecular and atomic resolution, AFM stepped beyond a shortcoming of the STM and opened the door to an exceptionally broad range of scientific fields – physics, materials science, engineering, chemistry, biology, medicine and beyond, establishing  AFM as an indispensable nanotool.

AFM’s central strength lies in its operational principle: a sharp tip, integrated in a microcantilever, measures  forces interacting with a surface with extraordinary sensitivity, converting these minute interactions into topographic maps with unprecedented resolution. Researchers can study samples in ultrahigh vacuum, ambient conditions, liquids, controlled atmosphere, at any temperature level making AFM also uniquely suited for biological and soft-matter studies. This adaptability drove early enthusiasm, and continuous technological refinements transformed AFM from a delicate research prototype into a routine analytical instrument.

A major driver of AFM’s rise has been its expanding modes of operation. AFM now measures a whole conglomerate of atomic forces, e.g mechanical, electrostatic , van der Waals, magnetic, friction and chemical interactions at the nanoscale. Techniques such as contact mode, non-contact dynamic mode (tuning fork), tapping mode, Kelvin force mode,  peak-force and off- resonance wave mode, quantitative nanomechanical mapping have effectively turned AFM into a multifunctional toolbox rather than a single instrument. Each new mode extended AFM’s reach into previously inaccessible scientific questions, reinforcing its reputation as a platform rather than a static technology.

Another reason for AFM’s enduring power is its synergistic integration with other methods.  Correlative AFM–optical microscopy, AFM–Raman spectroscopy, SEM Scanning electron microscopy, HIM helium ion microscopy and other methods have enabled  studies in a plethora of scientific  processes at the nanoscale and thus provide more comprehensive data than a single technique can. These  systems have kept AFM at the forefront of nanoscience, even since competing techniques such as super-resolution optical microscopy and advanced electron microscopy have advanced dramatically.

In biology AFM’s single-molecular spectroscopy revolutionized biological and materials science by allowing direct manipulation and measurement of individual molecules, providing insights into their mechanical properties, folding pathways, and interactions. High speed AFM opened up the time domain of chemical activity by monitoring the cellular machinery at the nanoscale with milliseconds resolution. Ultra-rapid and highly sensitive nanomechanical cantilever array sensors impacted medical diagnostics by surpassing time-consuming current gold standards.

Today, forty years after its invention, AFM remains unmatched in its combination of spatial resolution, environmental versatility, and multifunctionality. Its ability to probe surfaces physically, electrically, biologically and chemically—often simultaneously—has made it the cornerstone of nanoscale characterization. Far from being surpassed, AFM continues to innovate, proving that its fundamental principle is robust, adaptable, and with the integration of machine learning and AI remarkably future-proof.