Spectroscopic studies of integrated GaAs/Si heterostructures

The purpose of the study is to investigate the effect of a new type of compliant substrates based on an AlGaAs superstructure layer (SL) and a protoporous Si (proto-Si) layer formed on a crystalline Si ($c$-Si) layer on the optical properties of an epitaxial GaAs layer grown by metal–organic chemical vapor deposition. It is for the first time shown that the low-temperature growth of high-quality epitaxial GaAs films can be conducted using SL/proto-Si compliant substrates. The introduction of a SL layer in addition to proto-Si into the composition of the compliant substrate makes it possible to mitigate a number of negative effects of low-temperature growth, to reduce the level of strains in the epitaxial layer, to protect it from self-doping with Si atoms, to reduce the number of technological operations of the growth of transition buffer layers, to improve the structural and morphological characteristics of the epitaxial layer, and to attain good optical characteristics of the layer. The GaAs/Si heterostructures are studied by Raman spectroscopy, photoluminescence measurements, and optical transmission–reflection spectroscopy. The data will serve as an important material for understanding the fundamentals of the physics and technology of integrated III–V/Si heterostructures and for facilitating their use in optoelectronic devices.