*GaAs Compounds Heteroepitaxy on Silicon for Opto and Nano Electronic Applications DOI: http://dx.doi.org/10.5772/intechopen.94609*

the defects before growth of the III-V active layer. 2) Selective area epitaxy in dielectric cavities (SiO2,SiN, … ) formed by standard technological steps (deposition, lithography, etching, … ). In this last approach, the threading dislocation (TD) propagation is geometrically limited in one direction by the sidewalls of the patterns. These two majors will be described more deeply in the following paragraphs.
