Direct Heteroepitaxy of Orientation‐Patterned GaP on GaAs by Hydride Vapor Phase Epitaxy for Quasi‐Phase‐Matching Applications

Heteroepitaxial growth of orientation‐patterned (OP) GaP (OP‐GaP) on wafer‐bonded OP‐GaAs templates is investigated by low‐pressure hydride vapor phase epitaxy for exploiting the beneficial low two‐photon absorption properties of GaP with the matured processing technologies and higher‐quality substrates afforded by GaAs. –First, GaP homoepitaxial selective area growth (SAG) is conducted to investigate the dependence of GaP SAG on precursor flows and temperatures toward achieving a high vertical growth rate and equal lateral growth rate in the [110] and [10]‐oriented openings. Deteriorated domain fidelity is observed in the heteroepitaxial growth of OP‐GaP on OP‐GaAs due to the enhanced growth rate on domain boundaries by threading dislocations generated by 3.6% lattice matching in GaP/GaAs. The dependence of dislocation dynamics on heteroepitaxial growth conditions of OP‐GaP on OP‐GaAs is studied. High OP‐GaP domain fidelity associated with low threading dislocation density and a growth rate of 57 μm h −1 are obtained by increasing GaCl flow. The properties of heteroepitaxial GaP on semi‐insulating GaAs is studied by terahertz time‐domain spectroscopy in the terahertz range. The outcomes of this work will pave the way to exploit heteroepitaxial OP‐GaP growth on OP‐GaAs for frequency conversion by quasi‐phase‐matching in the mid‐infrared and terahertz regions.