All-epitaxial fabrication of thick, orientation-patterned GaAs films for nonlinear optical frequency conversion

Orientation-patterned GaAs (OPGaAs) films of 200 mum thickness have been gr own by hydride vapor phase epitaxy (HVPE) on an orientation-patterned templ ate fabricated by molecular beam epitaxy (MBE). Fabrication of the template s utilized only MBE and chemical etching, taking advantage of GaAs/Ge/GaAs heteroepitaxy to control the crystal orientation of the top GaAs film relat ive to the substrate. Antiphase domain boundaries were observed to propagat e vertically under HVPE growth conditions so that the domain duty cycle was preserved through the thick GaAs for all domain periods attempted. Quasiph ase-matched frequency doubling of a CO2 laser was demonstrated with the bea m confocally focused through a 4.6 mm long OPGaAs film. (C) 2001 American I nstitute of Physics.