In the grand map of science, exploring the microcosm has always been a cutting-edge and critical field. The scanning tunneling microscope (STM) is undoubtedly a powerful exploration tool in the hands of scientists, opening the mysterious door to the material world at the atomic scale for us.
The working principle of scanning tunneling microscope is based on the tunneling effect in quantum mechanics. Simply put, when an extremely thin probe is close enough to the surface of the sample, electrons will transfer from the probe to the sample surface or in the opposite direction without actual contact, creating a tunneling current. By precisely controlling the probe to scan the sample surface point by point and monitoring the changes in tunnel current in real time, the microstructure information of the sample surface can be obtained.
STM has high resolution, with a lateral resolution of up to 0.1 nanometers and a longitudinal resolution of up to 0.01 nanometers. This enables it to clearly distinguish individual atoms, allowing scientists to intuitively see the arrangement of atoms and their interactions for the first time. This observational capability has greatly promoted the development of multiple disciplines such as materials science, physics, and chemistry.
In the field of materials science, STM helps researchers gain a deeper understanding of the relationship between the microstructure and properties of materials. For example, by observing the arrangement defects of atoms on the surface of semiconductor materials, scientists can optimize the growth process of materials and improve the performance and stability of semiconductor devices. In physics, STM provides direct experimental methods for studying quantum phenomena such as quantum Hall effect and superconductivity, enabling people to have a deeper understanding of the microscopic quantum world. In the field of chemistry, STM can be used to study the microscopic processes of chemical reactions, observe dynamic processes such as adsorption, reaction, and product desorption of reactant molecules on catalyst surfaces, and provide important basis for developing efficient catalysts and understanding chemical reaction mechanisms.
In addition to its contribution to basic research, scanning tunneling microscopy also has a wide range of applications in industrial production. For example, in the semiconductor chip manufacturing process, STM is used to accurately detect and process the surface of silicon wafers, ensuring the high quality and performance of the chips.