Surface Structure Investigation Of Electronic Materials With Atomic Force Microscopy

Atomic Force Microscope are widely applied to the analysis on the films and surface microstructure because of its high spatial resolution and its less requirement for the surface of sample. In this paper a concise introduction of the theory and the characters of AFM has been given. And a brief introduction of the key skills and operation experience of the installation and debugging of AFM has been given too, including mostly the physical mechanism, scanning modes, optical detection system and resolvent of the difficulty during scanning.We have found better debugging methods of the optical detection system ,and proved the advantage of Tapping Mode in the surface topography measurement. Some solutions are proposed of the difficulties during scanning just as interference in the image, image drifting, periodic interference, scanning soft samples, and identifying mendacious images. And we have got good surface topography images through the data processing.TiO₂ low emission films were grown on glass substrate by dc reactive magnetron sputtering. AFM study on TiO₂ thin films deposited under various sputtering conditions, and optical transmittance spectra of TiO₂ thin films were measured. We have found that the TiO₂ thin films deposited under the higher oxygen pressure have the bigger crystallites and the higher infrared transmissivity.The compound semiconductors of III-V Group just as gallium arsenide (GaAs) have hige carrier transition ratio and good optoelectronic performance, so the study and application of these materials are very hot. And the defects caused by the surface damage of the materials have a great effect upon their performance.Because the positron annihilation spectroscopy can directly show the information of the defects in the materials, we have measured the positron life of the gallium arsenide samples of different surface roughness. And we have discussed the effect of the surface topography on the positron life.