Studies of lattice mismatch and threading dislocations in GaAs/Si grown by MBE

Characteristics of Strain-Induced InxGa1–xAs Nanowires Grown on Si(111) Substrates

“…3,4 Therefore, once a certain critical thickness is exceeded, strain relaxation proceeds by formation of misfit or threading dislocations. 5 Thus, it is very challenging to grow bandgap-engineered epitaxial thin films with a wide composition modulation on the same substrate such as In x Ga 1−x As on silicon (Si). 6 Onedimensional (1-D) heteroepitaxy on the other hand can accommodate mismatch strain through lateral strain relaxation, allowing NWs epitaxially grown on substrates with as much as 46% lattice mismatch.…”

Growth process and nanostructure of crystalline GaAs on Si(1 1 0) surface prepared by molecular beam epitaxy

“…However, there are inherent difficulties for the preparation of GaAs layer on Si substrates. The large lattice mismatch of 4.1% and the thermal expansion coefficient difference of 60% [6] will easily cause lattice defects such as threading dislocations which make the quality of the devices critically decrease [7][8][9]. Therefore, appropriate growth conditions at very early stage are required for the epitaxial growth because a coalescence of GaAs nuclei on Si substrate is a source of the threading dislocations at the early stage.…”

Effects of annealing and substrate orientation on epitaxial growth of GaAs on Si

“…The low temperature step with low V/III ratio ͑i.e., the flow rate of total group V precursors over that of total group III precursors͒ was essential to overcome the large lattice mismatch between GaAs and Si͑ϳ4%͒. 23 After the GaAs layer is initialized through the low temperature growth ͑can be considered as a nucleation step͒, the high temperature growth with high V/III ratio would improve the quality of the film. [9][10][11] Annealing process was also used in this study to improve both the surface morphologies and the internal crystal structure of the grown films.…”