AFM probe durability and tip wear
In atomic force microscopy (AFM), changes to the tip can change the image even when the sample stays the same. For surface topography, useful tip life is the period over which the tip retains a shape suitable for the measurement.
This guide explains how to recognise possible tip changes and compare useful lifetime without relying on scan count alone.
Published by Tiny Infinities · 21 September 2026
Updated 25 September 2026
Decide when the tip needs replacing.
An intact probe can have a damaged or broadened apex—the end that approaches the sample. A change may prevent two nearby particles from being distinguished before it affects a height measurement on a wide, flat step.
Choose a measurement check and an acceptable tolerance before starting. Record the result on a suitable reference with the initial probe, then repeat it at planned intervals. The replacement criterion should reflect the features you need to measure.
Distinguish wear, contamination and breakage.
- Wear removes material from the apex or contacting sidewall, changing the tip shape.
- Contamination adds material and can change both the effective shape and the interaction with the sample.
- Breakage changes geometry abruptly and can damage the tip or cantilever.
Broadened features or repeated shapes can suggest a tip problem, but feedback, drift and sample changes can produce similar symptoms. Image appearance alone does not identify the cause.
Check a suspected change.
- Save the raw data and settings. Compare forward and reverse scans for tracking problems.
- Recheck the setup. Review scan speed, feedback and interaction settings. Measure an appropriate reference to see whether the change also appears away from the original sample.
- Compare with a suitable replacement probe where practical. A different result helps identify the problem, but does not prove wear by itself.
Follow the probe and instrument manufacturer’s handling guidance. Cleaning must suit the material, coating and assembly; it cannot restore material lost through wear or breakage. Park Systems’ topography guide discusses tip condition and repeated measurements.
Compare lifetime under defined conditions.
Use the same sample type, reference check and replacement criterion. Record the mode, scan area, speed, environment and measurement history. Choose interaction settings and calibration appropriate to each probe and mode. Identical setpoints do not necessarily give equal tip–sample forces.
Report acceptable measurement time or scan distance, with the conditions. Repeat across several probes where practical and report the spread of results. NIST’s comparison of critical-dimension AFM tips illustrates a defined wear test; its numerical results apply to those tips and conditions.
When comparing productivity, count accepted datasets per total operating hour, including setup, checks, replacements and repeat scans. For speed limits, see the faster AFM scanning guide.
Match material and geometry to the task.
Durability depends on geometry, coatings, sample properties and operating conditions as well as tip material. A wear-resistant tip can still become contaminated or fracture. It must also reach the features being measured.
PolarTip is our silicon carbide (SiC) AFM probe line, developed around wear resistance and high aspect ratio, circularly symmetric tips. Its lifetime advantage remains to be measured. For a pilot, describe your sample, current probe and the observation that makes you replace it.