Influence of two-stage growth during the formation of GaAs/Si heterostructures for the creation of optoelectronic devices

The development of GaAs/Si heterostructures can be an important stage for use as solar cells, LEDs and lasers based on silicon substrates. At present, A3B5 compounds grown epitaxial on Si substrates are of great interest because of the monolithic integration of optoelectronic devices with Si-based microelectronics. High-quality epitaxial growth of heterostructures will not only ensure high mobility of the carrier materials, but also preserve the advantages of lightweight and inexpensive Si substrates with high mechanical strength and excellent thermal parameters. However, obtaining A3B5 compounds with high quality crystals of GaAs/Si heterostructures is a difficult task due to the formation of an antiphase domain boundary as a result of the growth of polar GaAs on a non-polar Si substrate. Because of this, a high density of penetrating dislocations arises due to the mismatch of the lattice parameters (4.1%), as well as the coefficient of thermal expansion (62%). (paper)