APPLICATION OF REAL-TIME LOW-ENERGY ION-SCATTERING SPECTROSCOPY TO HETEROINTERFACE FORMATION PROCESSES OF MOLECULAR-BEAM EPITAXIALLY GROWN III-V COMPOUND SEMICONDUCTORS

Coaxial impact-collision ion scattering spectroscopy (CAICISS) has been applied for the in situ analysis of heterointerface formation processes and related phenomena of III-V compound semiconductors in a CAICISS/molecular beam epitaxy (MBE) system where CAICISS was directly combined with an MBE chamber. We first demonstrate that CAICISS is useful for studying surface step structures by taking vicinal GaAs (100) surfaces as an example. The initial growth stages are then investigated regarding various lattice-mismatch (f) systems of AlAs on GaAs (f = 0.14%) and vice versa, GaAs on InP (f almost-equal-to 4%), and GaAs on InAs (f almost-equal-to 7%) and vice versa, in terms of the variations in the scattering intensity of incident ions. The obtained results are discussed especially from the view point of the growth mode (two-dimensional (2D) or 3D). During these processes, the exchange of atoms between the deposited films and the substrates is shown to be clearly observed for the AlAs/GaAs and GaAs/InAs systems based on the scattering intensity variation. These results are also discussed on the basis of other supporting data for the same phenomena observed by scanning tunneling microscopy and scanning microprobe reflection high-energy electron diffraction.