Showing papers by "Nikolay N. Mikhailov published in 2003"
TL;DR: In this article, a new generation of ultra high vacuum set, ultra-fast ellipsometer of high accuracy and automatic system for reproducibility of MCT Hs's growth on substrates up to 4" in diameter.
Abstract: View of basic and specific physical and chemical features of growth and defect formation in mercury cadmium telluride (MCT) heterostructures (HS's) on GaAs substrates by molecular beam epitaxy (MBE) was made. On the basis of this knowledge a new generation of ultra high vacuum set, ultra-fast ellipsometer of high accuracy and automatic system for control of technological processes was produced for reproducibility of MCT Hs's growth on substrates up to 4" in diameter. The development of industrially oriented technolgoy of MCT HS's growth by MBE on GaAs substrates 2" in diameter and without intentional doping is presented. The electrical characteristics of n-type and p-type of MCT HS's and uniformity of MCT composition over the surface area are excellent. The residual donor and acceptor centres are supposed as hypothetically tellurium atoms in metallic sublattice ("antisite" tellurium) and double-ionised mercury vacancies. The technology of fabricating focal plane arrays is developed. The high quality characteristics of infrared detectors conductance and diode mode are measured. Calculations of detector parameters predicted the improvement in serial resistance and detectivity of infrared diode detectors based on MCT heterostructures with graded composition throughout the thickness.
57 citations
21 Oct 2003
TL;DR: In this paper, the first results on a radiation stability investigation of MCT epilayers were presented, showing that MBE-grown epifilms have high radiation stability to an electron and gamma irradiation.
Abstract: The first results on a radiation stability investigation of mercury cadmium telluride (MCT) films, grown by molecular beam epitaxy (MBE) are represented. The samples were irradiated by high energy electron beams and gamma rays. Electrophysical and photoelectric parameters of MCT epilayers were measured. Volume material was measured too for the checking with MBE-grown one. MBE epifilms were irradiated on a pulsed electron accelerator with electron energy 1-2 MeV and current density less than 1 μA/cm2 for several fluences. Also MCT epitaxial heterostructures were irradiated by Co60 gamma rays. The same experiments were carried out for volume material. The analysis of dependence of Hall coefficient and conductivity from temperature and magnetic field (B) for p- and n- type samples was made. The irradiation of epilayers and volume MCT in the investigated range of irradiation fluences does not give both creation of electrical active damages in high concentrations and reconstruction of initial defects. Thus, MBE films of MCT have the high radiation stability to an electron and gamma irradiation. The obtained first results allow us to speak about high performance of explored MCT epilayers.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
5 citations
14 Apr 2003
TL;DR: In this paper, a new generation of ultra high vacuum set, ultra fast ellipsometer of high accuracy and automatic system for control of technological processes was produced for reproducibility growth of MCT solid solution heterostructures (Hs's) by molecular beam epitaxy (MBE).
Abstract: New generation of ultra high vacuum set, ultra-fast ellipsometer of high accuracy and automatic system for control of technological processes was produced for reproducibility growth of mercury cadmium telluride (MCT) solid solution heterostructures (Hs's) by molecular beam epitaxy (MBE). This system allows to grow MCT HS's on substrate up to 4" in diameter and used for future development technology of growth on Si substrate. The development of industrially oriented growth MCT HS's MBE on GaAs 2" in diameter is presented. The electrical characteristics of n-type and p-type MCT HS's MBE and uniformity of MCT composition over the surface area is excellent and satisfied for fabricating multielements arrays of high quality infrared devices.
TL;DR: In this article, a periodic surface microrelief in the form of an ordered system of extended waves with the characteristic period 0.1-0.2 μm has been detected on epilayers grown at increased temperatures.
Abstract: The surface microrelief of CdHgTe layers grown by molecular-beam epitaxy (MBE) method has been studied by means of atomic-force microscopy. A periodic surface microrelief in the form of an ordered system of extended waves with the characteristic period 0.1-0.2 μm has been detected on epilayers grown at increased temperatures. Angular dependencies of the conductivity at 77 K have been measured and the conductivity anisotropy has been detected with a minimum in the direction transverse to microrelief waves. A feature of the transmission system and the spectrum change after film annealing are observed. It is assumed that walls growing in the direction from the substrate to the surface are formed under microrelief waves slopes. Such structure can cause the observed feature of the transmission spectrum if the adjacent walls have different composition. In this work a calculation of spectral characteristics taking into account the influence of variable-gap composition and nonuniformity of the composition through the depth has been carried out.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.