Abstract
In this study, we focused on the changes of the Ge(100) surface when the 1064nm DPSS laser heating the surface. The surface temperature related to the angle that sandwiched by laser light and the surface normal vector of the sample. The temperature was also related to whether the laser light was through the viewport. To use the laser as a heating source, the colling rate of the sample surface was very fast. It can reduce the waiting time for cooling the sample, unlike traditional heating methods. Selected the Sb atom adsorbed on Ge (100) crystal face as the observation object, it can be divided into four types. Type C is our investigation. After the first 2.5 minutes laser heating, we can divide the molecular motion of Sb2 into six types (seven categories). There is about half of the pair of Sb2 molecules that tend to divide into two Sb2 molecules separately, and it moved perpendicular to the direction of the Ge dimer row. Secondary the position of the pair of Sb2 did not change. And by the second laser heating, the motion was difference with the first due to the different initial state. For the direction perpendicular to Ge dimer row, we explored the uneven distribution about the displacement diagrams. In addition, we wrote the programs to simulate the movement of molecules in order to understand the motion of pair Sb2 when the laser heating. Final, by different initial state, we calculated the activation energy by diffusion which was (a)1.005±0.054eV and (b)0.985±0.053eV. The force of attraction between two Sb2 was 20.0meV.