Temperature Dependence of Boron Adsorption during HBO2 Irradiation on Si(111) Surface Evaluated by Reflection High-Energy Electron Diffraction

Adsorption of boron on Si(111) surface during HBO2 irradiation was evaluated by reflection high-energy electron diffraction (RHEED). At the substrate temperature above 700°C, RHEED specular beam intensity decreased to a minimum value at boron coverage of 1/3 monolayer (ML), and then increased to the initial value (1 ML coverage). On the other hand, when the substrate temperature was below 700°C, intensity did not recover to the initial value due to the simultaneous surface oxidation. From the temperature dependence of the adsorption rate, the activation energy of the boron adsorption on Si(111) surface was estimated to be 1.2 eV.