Here's why:

* Atomic Resolution: STMs are capable of imaging surfaces at the atomic scale, meaning they can distinguish individual atoms.

* Quantum Tunneling: They work by utilizing the phenomenon of quantum tunneling, where electrons can pass through a barrier even if they don't have enough energy to do so classically. This allows the STM to "feel" the surface at the atomic level.

* Sharp Tip: The STM uses a very sharp tip that is brought extremely close to the surface. The tip's movement and the tunneling current are carefully controlled to create an image.

Other techniques like Transmission Electron Microscopy (TEM) can also provide images with high resolution, but they typically don't achieve the same level of atomic detail as an STM.