Ultrafast capture of the hot electron by the surface defects on the Si(001) surface

This paper investigates the process of the capture by the surface defects of the photoexcited electron on Si(001) at 100 K by means of the time-resolved two-photon photoelectron spectroscopy. A rapid decrease in sub-ps of the electron population at the conduction band and the simultaneous increase and subsequent decrease of the electron population at the defect states are observed. They are interpreted as the capture of the hot electrons in the conduction band by the surface defect states. The electron–temperature-dependence of the surface recombination velocity, which determines the capture rate of the bulk electron by the surface defects, is estimated assuming the multiphonon emission capture mechanism.