Two-dimensional materials like hexagonal boron nitride (hBN), graphene, and MoS₂ have properties that are highly sensitive to nanoscale structural features. Understanding these materials fully requires both surface morphology characterisation via atomic force microscopy (AFM) and atomic-scale structural analysis via transmission electron microscopy (TEM). The fundamental challenge is that these two techniques have conflicting requirements: AFM works on rigid and thick substrates, while TEM requires ultrathin suspended membranes. Currentlly, no single technique can provide both types of information simultaneously, and there is presently no established workflow to perform both measurements on the exact same region of a sample.

To address this gap, this project developed a complete correlative workflow enabling both AFM and TEM imaging to be performed on the same suspended region of a 2D material on a commercial TEM grid. This involved designing a custom mechanical holder that provides full support for stable AFM imaging on TEM grids. A region relocation method was also developed using optical microscopy as an intermediate reference, allowing the same membrane region to be reliably identified and imaged across both instruments. This project also determined the optimum AFM parameters such as setpoint and Z-gain to balance tip–sample interaction with membrane stability and tracking sensitivity.

Overall, the project has successfully demonstrated direct 1-to-1 correlation between AFM and TEM images on the same suspended membrane region which a significant first-of-its-kind achievement. A key insight from the project is that AFM phase images serve as an effective bridge between AFM topography and TEM contrast, helping reconcile information across the two modalities.