Consideration on the Quantitativeness of Reflection High Energy Electron Diffraction Intensity as a Tool to Monitor the Coverage of the Si(111) Surface by 7×7 Domains

Abstract

The quantitativeness of reflection high energy electron diffraction (RHEED) intensity as a high-speed tool to monitor nucleation and growth of 7 ×7 dimer-adatom-stacking-fault (DAS) domains on Si(111) surface rapidly quenched from a high-temperature disordered 1 ×1 phase has been investigated by comparing the time dependence of both RHEED intensity and scanning tunneling microscope (STM) images. The superlattice reflection intensity of RHEED normalized with that of uniform coverage increased gradually as a function of time after the quenching. The increase rate was higher at higher substrate temperature. A series of STM images revealed the transient aspect of the Si(111)7 ×7 reconstruction that a number of nuclei were randomly formed at the initial stage of growth, and the domain density decreased due to coalescence as the growth proceeded. The coverage by 7 ×7 DAS domains obtained from STM images was always higher than the normalized intensity of superlattice reflection, which showed that the intensity was reduced due to interference between randomly located DAS domains.