Heterointegration by molecular beam epitaxy: (In,Ga)As/GaAs quantum wells on GaAs, Ge, Ge/Si and Ge/Si pillars

► Integration of (In,Ga)As/GaAs QWs on GaAs, Ge/Si and Ge/Si micropillars is compared. ► On micropillars annihilation of anti-phase domains is found for vicinal substrates. ► Photoluminescence of different structures is studied and compared. ► By simulation PL peaks are assigned to interband transitions in three pairs of QWs.