The precision of these instruments stems from their ability to control and measure interactions at the atomic and molecular levels:
- AFM: Utilizes a cantilever with a sharp tip that interacts with the sample surface. The deflection of the cantilever is measured using a laser beam, providing high-resolution topographical data.
- SEM: Employs electron beams that interact with the sample, producing secondary electrons that are detected to form detailed images. The fine control of the electron beam contributes to its precision.
- TEM: Achieves atomic resolution by transmitting electrons through an ultra-thin specimen. The interaction of electrons with the sample elucidates its internal structure.
- STM: Measures the tunneling current between the tip and the sample surface, which is highly sensitive to atomic-scale variations.
