The evolution of atomic structure and chemical states of ultra-low energy high-dose Boron implanted Si via UV laser annealing*

One of the most critical issues in the nano-device fabrication is to confirm the atomic structure evolution of the ultrathin shallow junction. In this report, UV Raman spectroscopy, X-ray absorption near edge structure (XANES), X-ray photoelectron spectroscopy (XPS) and reflective second harmonic generation (RSHG) are used to analyze the pulse laser induced atomic structure evolution of ultralow-energy high-dose Boron implanted Si(110) at the room and cold substrate temperature. The formation of Si-B bond after the laser irradiation was indicated by a peak feature around 480 cm^-1 resolved in UV Raman spectra. Meanwhile, the evolution of absorption peak (~197 eV) in XANES and the red shift of binding energy of Si element (~99 eV) in XPS reveal that the changes in the chemical states of ultra shallow junction strongly correlate to the activation process of Boron implantation. These results were confirmed by RSHG measurement, which exhibits the form symmetrical Si-B bonds. The observation of HRTEM agreed with the substrate temperature effect in the recrystallization of Boron implanted region.