MOVPE growth of GaP on Si with As initial coverage

The growth of a GaP 50 nm layer on Si by metalorganic vapor phase epitaxy is studied using AsH3 and PH3 pre-exposure at low (550 °C) and high (800 °C) growth temperatures. The samples are characterized by transmission electron microscopy. The results obtained reveal that the use of As as a first coverage layer on top of misorientated Si-substrates favors the formation of a defect-free GaP epitaxial layer, for a wide range of AsH3 pre-exposure times using high growth temperature (800 °C), even though relatively low Si substrate annealing temperatures are used (850 °C) and no homoepitaxial Si layer was first grown. The procedure presented in this work reduces the thermal budget and complexity compared to most previous GaP/Si routines.