Group II Cubic Fluorides Dielectrics for 3-D Integration and GaAs-BasedOptoelectronic Structures

摘要

The epitaxial growth of CaxSr1-x,F2/GaAs(100) and GaAs/CaxSr1-xF2(100) isinvestigated. Optimum growth temperature of 530 deg C growth rate of 1 Angstrom/see and composition x=0.47 lead to very high crystallinity layers of mixed fluorides on GaAs. The growth of GaAs/Ca0.47SrO.053F2(100), rendered much more difficult by the morphology and faceting of the insulating surface, is substantially improved by modifying the fluoride surface by electron irradiation prior to GaAs growth, and by a two-step growth sequence where the interface GaAs is grown at low temperature (300 deg C). Finally, the patterning of the fluoride layer is performed by e-beam exposure. Features as small as 1 micron are drawn and developed on a 2000 A thick CaF2 layer, opening the possibility of using the fluorides for wave-guides or re-growth of small III-V features. Semiconductor/insulator interfaces; GaAs; Ca x Sr 1-x F2; molecular bean epitaxy.