Generation and suppression process of crystalline defects in GaP layers grown on misoriented Si(1 0 0) substrates

We have investigated the generation process of crystalline defects in GaP layers grown on Si substrates (GaP:Si) by molecular beam epitaxy (MBE) and migration enhanced epitaxy (MEE). Transmission electron microscopy observations revealed that few threading defects such as stacking faults and threading dislocations are detected ill GaP/Si by MEE. In addition a regular network of misfit dislocations was generated during the lattice relaxation process. On the other hand. stacking faults were generated in high density at the hetero-interface and threading dislocations as well as interfacial misfit dislocations were observed in CaP/Si by MBE. The generation of stacking faults would be related to the coalescence or expansion of isolated GaP islands and the presence of stacking faults would affect the generation of threading dislocations. (C) 1998 Elsevier Science B.V. All rights reserved.