Optical properties of GaN/SiC/$por$-Si/Si(111) hybrid heterostructures

Using a complex of structural and spectroscopic methods of diagnostics, the influence of a nanoporous-silicon ($por$-Si) transition layer on the optical properties of GaN layers grown on SiC/$por$-Si/$c$-Si templates by molecular-beam epitaxy with the plasma activation (MBE PA) of nitrogen is studied. It is shown for the first time that the MBE PA technology of the synthesis of GaN on a virtual SiC/$por$-Si/$c$-Si substrate provides a means for producing a GaN film of much higher structural and optical quality at a much lower growth temperature compared to those in similar studies, in which growth on porous Si substrates is demonstrated. The use of a $por$-Si layer makes it possible to improve the structural and morphological properties of the GaN epitaxial layer and to attain unique optical and electrical characteristics of the layer. The data obtained in the study will serve as an important basis for understanding the foundations of the physics of GaN/SiC/$por$-Si nanoheterostructures and for promoting their potential use in optoelectronics.