On the Growth of Thin-Film AlGaN/GaN Epitaxial Heterostructures on Hybrid Substrates Containing Layers of Silicon Carbide and Porous Silicon

Semiconductors - Abstract—In our work, we carry out a structural-spectroscopic study of AlGaN/GaN epitaxial layers grown by molecular-beam epitaxy with nitrogen-plasma activation on a hybrid...     

Effect of silicon on relaxation of the crystal lattice in MOCVD–hydride Al<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Ga<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>As:Si/GaAs(100) heterostructures

The X-ray diffraction and infrared spectroscopy data for MOCVD-hydride Al _x Ga_{1 − x} As:Si/GaAs(100) heterostructures and homoepitaxial GaAs:Si/GaAs(100) structures doped with Si to a content of up to ∼1 at % are reported. It is shown that, in the homoepitaxial heterostructures, the formation of alloys with Si yields a decrease in the crystal lattice parameters of the epitaxial layer and a negative lattice mismatch with the single-crystal substrate (Δa < 0). At the same time, the formation of quaternary alloys in the Al _x Ga_{1 − x} As:Si/GaAs(100) heterostructures is not accompanied by any pronounced strains in the crystal lattice. By introducing Si into the epitaxial layers of these heterostructures, it is possible to attain complete matching of crystal lattice parameters of the film and substrate in the appropriately chosen technological conditions of growth of the epitaxial layers.     

Structure and optical properties of heterostructures based on MOCVD (Al x Ga1 − x As1 − y P y )1 − z Si z alloys

Epitaxial heterostructures produced by MOCVD on the basis of Al _x Ga_{1 ? x} As ternary alloys with the composition parameter x ≈ 0.20–0.50 and doped to a high Si and P atomic content are studied. Using the high-resolution X-ray diffraction technique, scanning electron microscopy, X-ray microanalysis, Raman spectroscopy, and photoluminescence spectroscopy, it is shown that the epitaxial films grown by MOCVD are formed of five-component (Al _x Ga_{1 ? x} As_{1 ? y} P _y )_{1 ? z} Si _z alloys.     

Effect of Misorientation and Preliminary Etching of the Substrate on the Structural and Optical Properties of Integrated GaAs/Si(100) Heterostructures Produced by Vapor Phase Epitaxy

It is shown for the first time that the structural and optical functional characteristics of integrated GaAs/Si(100) heterostructures can be controlled by using misoriented Si(100) substrates and their preliminary etching. The growth of an epitaxial GaAs layer on a Si substrate without the formation of antiphase domains can be carried out on a substrate deviated from the (100) singular plane by an angle smaller than 4°–6° or without a transition layer of GaAs nanocolumns. Preliminary treatment of the silicon substrate by etching makes it possible to use it for the vapor-phase epitaxial growth of a single-crystal GaAs film with a considerably smaller relaxation coefficient, which has a positive effect on the structural quality of the film. These data are in good agreement with the results of IR reflectance spectroscopy and photoluminescence and ultraviolet spectroscopy. The features of the optical properties of integrated GaAs/Si(100) heterostructures in the infrared and ultraviolet spectral regions are also defined by the relaxation coefficient.     

Spectroscopic Studies of Integrated GaAs/Si Heterostructures

Semiconductors - 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...     

On the Phase Composition,Morphology, and Optical and Electronic Characteristics of AlN Nanofilms Grown on Misoriented GaAs(100) Substrates

Semiconductors - Thin AlN nanofilms are produced by reactive ion-plasma deposition onto GaAs(100) substrates misoriented with respect to the 〈100〉 direction to different degrees. It...     

Structural and spectral features of MOCVD Al x Ga y In1 ? x ? y As z P1 ? z /GaAs (100) alloys

The study is concerned with MOCVD epitaxial heterostructures grown on the basis of Al _x Ga _y In_{1 ? x ? y} As _z P_{1 ? z} quinary alloys in the region of alloy compositions isoperiodic to GaAs. By the X-ray diffraction technique and atomic force microscopy, it is shown that, on the surface of the heterostructures, there are nanometric objects capable of lining up along a certain direction. From calculations of the crystal lattice parameters with consideration for internal strains, it can be inferred that the new compound is a phase based on the Al _x Ga _y In_{1 ? x ? y} As _z P_{1 ? z} alloy.     

Properties of Compliant Substrates Based on Porous Silicon Formed by Two-stage Etching

Semiconductors - Abstract—Our work reports on the influence of etching modes and their combination on the design, microstructural and optical properties of compliant substrates based on...     

Structural and optical properties of heavily doped Al x Ga1 − x As1 − y P y :Mg alloys produced by metal-organic chemical vapor deposition

The high-resolution X-ray diffraction technique, Raman spectroscopy, and photoluminescence spectroscopy are used to study the structural, optical, and electron energy properties of epitaxial Al _x Ga_{1 ? x} As_{1 ? y} P _y :Mg alloy films grown by metal-organic chemical vapor deposition (MOCVD). It is shown that the introduction of a Mg impurity into the quaternary alloy provides high charge-carrier concentrations. A decrease in the growth temperature yields a decrease in the charge-carrier concentration in films doped with magnesium at a small gas-carrier flux of the acceptor impurity, whereas an increase in the flux results in an increase in the acceptor-impurity concentration, which is reflected in the character of the photoluminescence spectra.     

Structural and optical properties of low-temperature hydride-MOCVD AlGaAs/GaAs(100) heterostructures based on omission solid solutions

X-ray diffraction, scanning electron microscopy, and IR reflectance spectroscopy were used to study properties of epitaxial low-temperature hydride-MOCVD AlGaAs/GaAs (100) heterostructures. It was found that the variation in the AlGaAs alloy lattice’s parameter with Al content does not obey the classical Vegard’s law, and the lattice parameters are smaller than those of GaAs.