Park Atomic Force MicroscopeAs a core device for nanoscale characterization, its faults are mainly concentrated in three types of issues: imaging quality, probe interaction, and system response. The following are self inspection and quick solutions adapted to laboratory scenarios to ensure the accuracy of test data.

1. The image is full of noise or artifacts: If only a few samples are like this, it is mostly due to sample contamination. Soft samples can be frozen and fixed to avoid wrinkling, while powder samples can be cleaned with nitrogen after ethanol ultrasound; If all samples have noise, the probe needs to be checked. Worn or contaminated probes need to be replaced. Silicon carbon needles are selected for nanostructures, and silicon nitride carbon needles are adapted for soft materials. In addition, the scanning speed of soft samples can be reduced to below 1Hz, and hard materials should not exceed 2Hz. At the same time, nearby centrifuges and other equipment can be turned off, and environmental vibrations can be isolated with the help of an anti vibration table.

2. Repeated lines or stripes appear in the image: 50Hz electrical noise will produce repeated lines, and the scanning frequency can be adjusted or tested during low electricity consumption periods such as late night; If it is laser interference, it is mostly due to the reflection of laser from high reflection samples entering the detector. Replacing the probe with aluminum or gold reflective coating can eliminate the interference. If the stripes are caused by loose particles on the surface of the sample, the sample needs to be cleaned again and the sample preparation process optimized to reduce residual impurities.

3. Probe cannot approach the sample normally (false feedback): The phenomenon is image blurring and defocusing, mostly due to thick contamination layers on the sample surface or strong electrostatic forces between the probe and the sample. During self inspection, observe whether there are obvious stains on the surface of the sample, wipe the sample with anhydrous ethanol and dry it; For the issue of electrostatic force, it can be discharged through the device's built-in static elimination function or tested in a low humidity environment.

4. Abnormal scanning height or inability to identify steep structures: If the surface roughness of the sample exceeds the Z-phase range of the instrument by about 10 μ m, the sample needs to be cut or a flat area selected for testing; If the imaging of structures such as deep grooves is distorted due to insufficient aspect ratio of the probe, replacing the HAR probe with a high aspect ratio can allow it to penetrate deep into the bottom of the groove to restore the true morphology and avoid measurement deviation caused by sidewall obstruction.

5. Signal transmission interruption or data abnormality: When there is no data feedback from the central control, first check the connection between the equipment and the computer, and replace the damaged shielded cable in a timely manner; If there is data drift, perform two-point calibration with high-purity nitrogen and standard samples every 3-6 months. If the electrical module test is abnormal, check the contact status between the electrode and the sample, ensure that the electrolyte covers the electrode, and if necessary, re fix the electrode joint.

Daily cleaning of probes and lenses is required every month, and the lenses should be lightly wiped with lens paper dipped in anhydrous ethanol; Check the vibration isolation table and gas source status every quarter, and place them in a drying oven to prevent moisture from affecting components when they are idle for a long time, which can significantly reduce the occurrence rate of failures.