A. I. Izhnin

Bio: A. I. Izhnin is an academic researcher from Tomsk State University. The author has contributed to research in topics: Photoluminescence & Molecular beam epitaxy. The author has an hindex of 6, co-authored 14 publications receiving 96 citations.

Defect structure of HgCdTe films grown by molecular beam epitaxy on Si substrates

Abstract: An ion milling-assisted study of defect structure of HgCdTe films grown by molecular beam epitaxy on Si substrates was performed. The films appeared to contain initially neutral Te-related defects with concentration of 1017 cm−3, typical of HgCdTe. The concentration of residual donors was found to be quite low ((3–8) × 1014 cm−3). Specific to HgCdTe/Si technology appeared to be a considerable number of stacking faults, which affected the carrier mobility in n-type material. These defects can be annealed in He atmosphere at 230 °C, and after ion milling the electrical parameters of n-type HgCdTe/Si films approach those of high-quality bulk crystals.

Donor doping of HgCdTe for LWIR and MWIR structures fabricated with ion milling

Abstract: Ion milling was used to establish the minimum donor doping level Nmd required for obtaining n-regions with reproducible electron concentration in HgCdTe-based LWIR and MWIR device structures fabricated with ion treatment. The experiments were performed on n-type films grown by molecular beam epitaxy, un-doped and in situ doped with indium with the concentration NIn = 5 × 1014–1017 cm−3. A study of the electrical properties of the milled films showed that Nmd comprised ~2 × 1015 cm−3 for the LWIR and ~5 × 1015 cm−3 for the MWIR films. In the films with NIn exceeding these critical values, the electron concentration after the milling strictly followed the doping. A need for consideration of the disintegration of the milling-induced defects is also shown.

Analysis of the photoluminescence spectra of Cd x Hg 1–x te heteroepitaxial structures with potential and quantum wells grown by molecularbeam epitaxy

Abstract: A theoretical model for description of the band diagram and the photoluminescence spectra of heteroepitaxial structures (HES) based on Cd x Hg1–x Te (MCT) with potential and quantum wells (QW) grown by molecularbeam epitaxy (MBE) is developed. A special feature of the model is that the model takes into account the dependence of electron affinity on the MCT composition and temperature as well as the dependence of the electron concentration in intrinsic MCT and hole concentration in vacancy-doped MCT. The calculations are made and the results are compared with the experimental photoluminescence spectra of various structures with QW reported in the literature.

Acceptor states in heteroepitaxial CdHgTe films grown by molecular-beam epitaxy

Abstract: The photoluminescence method is used to study acceptor states in CdHgTe heteroepitaxial films (HEFs) grown by molecular-beam epitaxy. A comparison of the photoluminescence spectra of HEFs grown on GaAs substrates (CdHgTe/GaAs) with the spectra of CdHgTe/Si HEFs demonstrates that acceptor states with energy depths of about 18 and 27 meV are specific to CdHgTe/GaAs HEFs. The possible nature of these states and its relation to the HEF synthesis conditions and, in particular, to the vacancy doping occurring under conditions of a mercury deficiency during the course of epitaxy and postgrowth processing are discussed.

Photoluminescence of HgCdTe nanostructures grown by molecular beam epitaxy on GaAs

Abstract: Photoluminescence (PL) of HgCdTe-based hetero-epitaxial nanostructures with 50 to 1100 nm-wide potential wells was studied. The nanostructures were grown by molecular beam epitaxy on GaAs substrates. A strong degree of alloy disorder was found in the material, which led to the broadening of the PL spectra and a considerable Stokes shift that could be traced up to temperature T∼230 K. Annealing of the structures improved the ordering and led to the increase in the PL intensity. A remarkable feature of the PL was an unexpectedly small decrease of its intensity with temperature increasing from 84 to 300 K. This effect can be related to localization of carriers at potential fluctuations and to the specific character of Auger-type processes in HgCdTe-based nanostructures.

Stimulated emission from HgCdTe quantum well heterostructures at wavelengths up to 19.5 μm

Abstract: We report on stimulated emission at wavelengths up to 19.5 μm from HgTe/HgCdTe quantum well heterostructures with wide‐gap HgCdTe dielectric waveguide, grown by molecular beam epitaxy on GaAs(013) substrates. The mitigation of Auger processes in structures under study is exemplified, and the promising routes towards the 20–50 μm wavelength range, where HgCdTe lasers may be competitive to the prominent emitters, are discussed.

HgCdTe-based heterostructures for terahertz photonics

Abstract: Due to their specific physical properties, HgCdTe-based heterostructures are expected to play an important role in terahertz photonic systems. Here, focusing on gated devices presenting inverted band ordering, we evidence an enhancement of the terahertz photoconductive response close to the charge neutrality point and at the magnetic field driven topological phase transition. We also show the ability of these heterostructures to be used as terahertz imagers. Regarding terahertz emitters, we present results on stimulated emission of HgCdTe heterostructures in their conventional semiconductor state above 30 THz, discussing the physical mechanisms involved and promising routes towards the 5–15 THz frequency domain.

Terahertz photoconductivity of double acceptors in narrow gap HgCdTe epitaxial films grown by molecular beam epitaxy on GaAs(013) and Si(013) substrates

Abstract: The energy spectra of the mercury vacancy, the most common acceptor in HgCdTe material, is studied via numerical calculations and low temperature photoconductivity (PC) measurements of 'vacancy-doped' HgCdTe films with low cadmium content Since the Hg vacancy is known to be a double acceptor, the model for the helium atom was adopted for degerate valence band of zinc blende semiconductors to classify the observed PC bands This approach provides a fairly good description of the photoionization of both neutral and singly-ionized vacancy when the central cell potential is taken into account