A Novel Growth Method for High Quality GaAs/CaF2/Si(111) Structures by Using “Type-A” CaF2 Film

Abstract

ABSTRACTControl of epitaxial relationship of CaF2 films grown on Si(111) substrates was considered to be important to improve surface morphology and crystallini ty of GaAs films on CaF2/Si(111) structures. We successfully grew CaF2 films with the “type-A” epitaxial relationship on Si(111) substrates, that is, the crystallographic orientation of the CaF2 films were aligned in the same direction as that of the Si(111) substrates. These “type-A” CaF2 films were grown by a two step growth method. It was found that surface morphology of GaAs films on the CaF2/Si(111) structures was drastically improved by growth of the “type-A” CaF2 films.