Direct Heteroepitaxy and Selective Area Growth of GaP and GaAs on Si by Hydride Vapor Phase Epitaxy

Direct heteroepitaxy and selective area growth (SAG) of GaP and GaAs on Si(100) and Si(111) are implemented by low-pressure hydride vapor phase epitaxy (LP-HVPE), which are facilitated by buffer layers grown at 410-490 degrees C with reactive gas mixing directly above Si substrates. High-density islands observed on GaP buffer layers on Si result in rough morphology and defect formation in the subsequent GaP layers grown at 715 degrees C. The impact of growth temperature of GaAs buffer layers on the crystal quality of GaAs/Si is studied. A decreased nucleation temperature significantly improves the morphology and crystalline quality of the overall GaAs growth on Si. It is observed that Si(111) substrates are favorable for both GaP and GaAs growths in comparison with Si(100). In SAGs of GaP/Si and GaAs/Si, the high selectivity innate to HVPE is maintained in the used unconventional growth regime. The spatially resolved photoluminescence mapping reveals the material quality of GaAs/Si is enhanced by defect filtering by SAG. The outcomes of this work will pave the way of III-V/Si integration realized by cost-effective HVPE for photonic device applications.