MORPHOLOGY OF THIN SRF2 FILMS ON INP(111) STUDIED BY REFLECTION HIGH-ENERGY ELECTRON-DIFFRACTION

We studied the growth of SrF2 on InP(111) by reflection high-energy electron diffraction (RHEED). This paper compares the surface and bulk crystalline structures of 35 Angstrom thick SrF2 grown on two InP(111) surfaces prepared in different ways. HF-etching of the InP(111) substrate resulted in a rough surface, whereas an As-treatment produced a flat surface without any superstructure. After being annealed at 500 degrees C for 10 min the SrF2 film deposited on the HF-etched surface showed a texture, whereas the film deposited on the As-treated InP(111) surface uas epitaxial and even had no twinning.