RD&P Center ORION has developed a FPA technology based on planar HgCdTe photodiode arrays and custom designed silicon integrated readout circuits. Photovoltaic detectors array made on mercury cadmium telluride liquid phase epitaxy layer and silicon readout circuits are linked by indium bumps on sapphire interconnection substrate. Cooled silicon readout circuits have been made by n-MOS technology. This paper describes a generic architecture and development results of the linear 3 - 5 micrometers and 8 - 12 micrometers waveband TDI scanning IR FPA of 4 X 48, 2 X 96, 4 X 128, 2 X 256 formats. Performances of photovoltaic arrays based on MCT epilayers are introduced. Test methods and typical investigation results of hybrid FPA in the TDI mode are described. For 8 - 12 micrometers wavelength range detectivity is greater than (1-2) X 10¹¹ cmW^-1Hz^1/2 for 4 X 48 and 4 X 128 FPA with four TDI elements and greater than (7-10) X 10¹⁰ cmW^-1Hz^1/2 for 2 X 96 or 2 X 256 FPA with two TDI elements.

LWIR staring 128 X 128 and 384 X 384 focal plane arrays (FPA) have been developed and investigated. FPAs have been manufactured on the base of mercury cadmium telluride epitaxial layers grown both by liquid phase epitaxy and molecular beam epitaxy. The photodiode array was bonded via the indium bumps to the silicon MOS-multiplexer, which ensure reading, integration and output of the photosignals from the focal plane. Performances of FPAs produced by these different epitaxial methods are analyzed.

We theoretically study physical processes in new promising hybrid IR FPAs based on HgCdTe p-n junctions and analyze them ultimate performance for 3 - 5 micrometers and 8 - 10 micrometers spectral ranges. Architecture of these FPAs are much simpler than that of existing FPAs: IR-sensitive HgCdTe p-n junctions are used as switches themselves, and capacitors used as strong elements occupy all the area under each p-n junction. These capacitors can be produced on the base of dielectrics with relatively high permittivity (of TiO₂, type or integrated ferroelectrics). In contrast to CCD and CID, the proposed FPA does not use charge transfer between electrodes separated in space. We formulate requirements to the parameters of photosensitive elements and storage capacitors to reach the largest integration time and threshold characteristics close to the theoretical limits. It is shown that in principle the considered FPAs have unique parameters and 1/f noise of amplifiers can be suppressed in them. FPA for 3 - 5 micrometers spectral range with p-n junction of 20 X 20 micrometers ² area can operate in BLIP mode at background temperature 300 K;its photosignal integration time equal to the persistence of human eye and format can reach 1024 X 1024 pixels. For 8 - 10 micrometers range these parameters are 300 microsecond(s) and 256 X 256 pixels, respectively, when TiO₂ storage capacitors are used.

Crosstalk in 32 X 32 and 128 X 128 HgCdTe staring focal plane arrays consisting of HgCdTe photodiode array bonded with silicon MOS-multiplexer by indium bumps have been investigated. The experimental results of crosstalk caused by the diffusion of photogenerated carriers, inverse surface layers and photoresistance effect in HgCdTe substrate are presented. The influence of drain-source leakage in multiplexer switching transistors on crosstalk is discussed.

Single element mercury cadmium telluride (MCT) LWIR and MWIR photodiodes have been investigated. High speed up to 1 GHz heterodyne mode detectors are included. Topology and technology features of 32 X 32, 128 X 128, 384 X 288, 4 X 16, 4 X 16, 4 X 48, 2 X 96, 4 X 128, 2 X 256 LWIR and MWIR focal plane arrays (FPA) produced on the base of MCT crystals and epitaxial layers are discussed. Temporal and thermal stability of MCT photodiodes and future FPA development are analyzed.

The method of IR detector sensitivity spatial distribution restoring from the experimentally measured photosignal dependence versus optical spot position and known optical spot spread function is developed and experimentally investigated.

Current-voltage characteristics of LN2 cooled MCT p-n tunnel junctions have been investigated. The negative differential conductance takes place at negative total current due to photocurrent bias. This gives possibility of current oscillation without external electric power.

The different type design of sensitive elements for photoconducting (PC) and photoelectromagnetic (PEM) infrared detectors for attention have been offered. For uncooled PC and PEM detectors on the base of HgCdTe by the sensing elements as meander-type have been considered. For PC IR- detectors the construction with two-side metallization of the contact areas of the element are represented. These detectors high sensitivity are demonstrated.

Results of studying chemical PbSe layers deposited on photoglass substrates with selective interference dichroic mirrors increasing photoactive absorption in 4 micrometers and more spectral range are given. Integral D* and S_u have higher values in comparison with photolayers manufactured by traditional methods.

A new photodetecting assembly intended for registration of ultraviolet radiation in the spectral range 0.28...0.4 micrometers is described. The special features of a new device are small dimensions (body diameter of 15 mm, and length less than 10 mm), presence of three independent channels with low-noise amplifiers and band electrical filters, and additional correction of spectral characteristic by optical filter.

We report on the fabrication and characterization of ultraviolet photodetectors with Schottky barrier based on semiconductor GaP, GaP_xAs_1-x and GaAs. As row materials are used n-n⁺-type epitaxial structures. Base parameters of the photodetectors are demonstrated.

It is shown that near-surface variband layers can afford the maximally possible photomodulation of conductivity of CdHgTe n-type samples for 8 - 12 and 3 - 5 micron light wavelengths. The photomodulation efficiency will be identical to that for absence of surface recombination. This is caused by the shaping of such photocarrier distribution which inhibits photocarrier diffusion to the surfaces even under small variband fields E_var. Therefore the number of defects in the variband layers can be decrease significantly at the cost of decrease in the gradient of mole composition of these layers.

Cadmium mercury telluride (MCT) photodiodes stability has been investigated. Possible reasons of photodiodes performances degradation are analyzed. High temporal and thermal stability at storage temperature up to 70 degree(s)C of ion implanted MCT photovoltaic detectors is shown.

The influence of ionizing irradiation of different kind- imitation factors of nuclear explosion and proton irradiation on photoelectric properties of photodiodes on the base of indium selenide have been investigated. Photoreceivers was exposed to ionizing irradiation of following kinds: influence of damaging factors of nuclear explosion with neutrons energy of E_n > 0.1 MeV and fluence of 3 (DOT) 10¹² cm^-2 and pulse gamma- irradiation of power 1 (DOT) 10¹⁰ R/s; influence of proton irradiation with fluence 5 (DOT) 10¹³ cm^-2. It is shown that pulse gamma- and neutron- irradiation essentially acts on monochromatic and volt-watt sensitivities of photodiodes, increasing them about 20 - 40%. In short-wave region of a spectrum significant increasing is observed, while sharp decreasing in sensitivity in long-wave region occurs. Non-uniformity of amplitude-frequency characteristics increases up to 40 - 65%. This fact is explained by the widening of space-charge region in photodiodes. This result in decreasing the capacity of p-n-junction and widening of transmission band. Results obtained may be used for the fabrication of photodiodes, operating in near IR-region of spectrum.

In the article the state-of-the-art of development of night vision and thermovision devices is briefly stated, the paths and concepts of further development of these kinds of engineering are shown, the major were in process development of new kinds of night engineering on the basis of advanced achievements in development and creation of Image Intensifiers and photodetectors are listed. The comparative analysis of equipment of night vision and thermovision devices of Russian and foreign armies is shown.

Outdoor test results (with distance up to 10 km) of the experimental IR camera with IR SB CCD with 256 X 256 pixels of range 3 - 5 (mu) are presented. It is shown that MTF of the camera was determined by IR SB CCD, Nyquist frequency was set by the geometrical sizes of an array pixels and any decrease characteristic spatial frequency was not observed. The response time of the experimental MTF magnitude and estimations of limiting angular speed of objects (omega) ₀ is congruent to 100 rad/sec is made. With use of suggested small contrast discrimination method the fine details NEDT was equal 48 - 100 mK at standard frame time. Test results shows the fitness of IR SB CCD camera for fast moving registration.

IR imager have been developed and investigated. IR imager consists of mercury cadmium telluride 128 X 128 staring focal plane array bonded by indium bumps with silicon MOS- multiplexer, split-Stirling cooler, electronic signal processor. Noise equivalent temperature difference NETD is less than 0.1 K.

Detailed theoretical analysis of the dependence of the weak optical radiation gain on the concentration of recombination centers in intrinsic impurity-type-recombination photoconductors with extracting current contacts is carried out. The model of a single recombination level is considered. It is shown that the carrier lifetimes and the gain may strongly non-monotonically depend on the concentration of recombination impurity atoms. The conditions under which these effects take place are determined, and the physical mechanisms responsible for it are found out. The formulae for the locations of the extrema of the considered dependences are obtained. It is shown that the gain splash value depends non-monotonically on the applied voltage at the cost of photoinduced space charge. The maximally possible photogain is evaluated.

A physical model for explanation of experimentally observed effect of avalanche noise-factor F decrease in MIS-type heterostructures upon a multiplication factor increase is offered. The model is based on the assumption that carriers are retarded near heteroboundary due to trapping by a potential well (for a example in SiO₂/Si and TiO₂/Si) or by surface levels. The calculation results correlate numerically with the experimental data.

Under conditions of nonequilibrium carriers recombination through two-level impurity and of weak optical radiation photocurrent dependence on recombination impurity concentration N in the intrinsic photoresistor with extracting contacts is theoretically analyzed. It is shown that like in single-level impurity case there may be effect of gigantic photocurrent splash upon increasing in N. It is determined that photocurrent does not saturate with increasing electric field strength for a wide section of N preceding to the point of splash unlike the single-level impurity case. It is found out that the photocurrent dependence on two-level recombination impurity concentration may have two maxima. A physical interpretation of the results obtained is given.

It is shown that a choice of the thermoresistor thermal time constant of the order of frame time is not sufficient condition for achieving the signal to noise ratio which corresponds to the integration time of the order of frame time. Conditions are found when one get improving signal to noise ratio approximately (root)M times in comparison with the case without signal integration (M number of pixels in the array). Sensitivity (NEP for a monochromatic signal and NETD) of IR photodiode array with signal integration by the thermoresistors are found for state-of-the-art parameters. Comparison is made of this characteristics with characteristics of analogous array without signal integration, with integration by capacitor, with characteristics of bolometric array.

Using Burgess's variance theorem, it is shown that at binomial transitional characteristics, variances of photons and photoelectrons have identical functional form when photons have negative-binomial or Poisson distribution function. By direct calculation it is obtained that in this cases photoelectrons distribution function reproduces that of photons that is photoelectrons distribution function has negative-binomial or Poisson form.

A choice of sensitive element material for uncooled microbolometric array dependents on the ultimate array parameters to a great extent. This paper presents the results of studies of sandwich and planar bolometric structures based on aSi:H and VO₂ films accordingly. The aSi:H films were fabricated by plasmachemical vapor-phase deposition and VO₂ films were prepared by reactive magnetron ion-plasma sputtering. Sandwich structures with area 100 X 100 micrometers have a resistance of 20 k(Omega) and temperature coefficient of resistance (TCR) of approximately equals 2%/K at 25 degree(s)C. Planar structures with operating section dimensions of 100 X 70 micrometers have TCR of 2.9%/K at the same resistance. The methods of contact noise reduction are found for both type structures. Sandwiches constructed to act as an optical cavity absorb 80% of radiation at 8 micrometers wavelength. It is shown that the planar structures absorption of 50 - 80% can be reached in the 8.5 - 10 micrometers band.

It is shown theoretically and experimentally that the internal quantum efficiency dependence on quantum energy differs strongly from the standard dependences, described by the Fowler's theory, within the conditions of the hot electron resonance appearance. The problem of the `cooling path' increase for metal silicides and semiconductors is discussed. The advantages of recent IR SB CCDs from the technical parameter optimization standpoint are denoted.

Hg_1-xCd_xTe single crystals with a diameter of more than 50 mm have been grown at a constant temperature by recrystallization of preliminarily synthesized charge under the conditions of permanent melt feeding with the solid phase. This method has been mathematically modelled. The composition homogeneity and electrical and structural properties of the single crystals for different growth conditions have been studied.

Original technique of the obtaining of epitaxial films of the A⁴B⁶ type semiconductors and p-n structures on their base in superhigh vacuum by the `hot wall' method have been developed. The conditions of the growth of epitaxial films of Pb_1-xSn_xTe (x equals 0,2) PbTe_1-ySe_y (y equals 0,08) in superhigh vacuum are defined and peculiarities of their growth on various substrates have been established. In the order of increasing of charge carrier mobility and improving structure perfection of the films additional compensating source of halogen vapors was used. Crystallic structure of the obtained epitaxial films and p-n structures have been investigated by electronographic, electronomicroscophic and X-ray diffractometric methods. Isoperiodical heterostructures of p-Pb_1-xSn_xTe (x equals 0,2) - n-PbTe_1-ySe_y (y equals 0,08) were obtained. On the base of heterostructures obtained photosensitive elements with parameters: R_o A_77k equals 0,6 - 0,8 Ohm.cm²; 1_max equals 10,5 micrometers were fabricated.

Films of Pb_1-xSn_xSe (x equals 0,03 divided by 0,07) doped by In atoms have been grown on the substrate of BaF₂(111,100) by a molecular beam condensation method. Peculiarities of growth and their electrophysical properties have been investigated. Electronographic, X-ray diffractometric and electron-microscopic methods, obtained the data on structure of films. Epitaxial films by the thickness about 1 divided by 1,5 micrometers were obtained at the substrate temperature equal (400 divided by 450) +/- 0,5C degree(s). The magnitudes of half-width of swinging curve of the X-ray diffraction changed within limits of W_1/2 equals 100 divided by 200 angl.s. The concentration and mobility of the charge carriers were n equals (2 divided by 5) (DOT) 10¹⁶ cm^-3 and (mu) equals (2 divided by 3) (DOT) 10⁴ cm²/V(DOT)s, accordingly. Films had a mirror-smooth surface by planes of growth (111,100) on various substrates. The temperature dependencies of Hall coefficient R_H of the Pb_1-xSn_xSe doped by indium (0,3 divided by 0,5 mass %) with different concentration of the charge carriers were investigated. It is shown that mobility determined from Hall and electroconductivity measurements in the impurity conductivity region changes on degree-low (mu) approximately T^-v, where v equals 1,6 divided by 2,5.

In order to improve quality of photodetectors and photodetective assemblies two new cryo- and chemically resistant adhesives were developed: epoxy-silico-organic adhesive `(Phi) X-5P' and acrylic `OPHOH-2' adhesive for gluing of CdHgTe wafers to a substrate `XCK-H' vacuum-tight modified adhesive is used for attaching of inlet windows and glass holder elements. `OPUOH-65' vibration damping thixotropic composition was developed for mounting of multi- layer printed circuits.

The conditions of small dispersive phase generation in the crucible type source of indium and of tin ions are investigated. The microdroplet emission cause by threshold means the instability of ion beam current. The charge particle dimension spectrum is continuous in the diapason up to 20 angstroms to 400 angstroms but the frequency spectrum of oscillations is discrete in the diapason up 2 MHz to 30 MHz. The observated characteristics of liquid metal ion sources are interpreted in the frame of model of field stream ionization and of thermal liquid dispersion in the strong electrical field.

The paper summarizes the results on developing and testing numerical algorithms and software for computer modeling of emission electron beam devices. As examples, some numerical experiments carried out with the newly developed Applied Program Package `CHARGE' are presented and discussed.

Electron-beam processing of insulating materials faces some difficulties connected with electric charge accumulation during electron irradiation. In this paper investigation of charging dynamics of glasses subjected to electron beam, is presented. It was found that secondary emission from the surface is not the only way of excess charge vanishing in some insulating materials. Under certain circumstances, strong electric field of introduced charge may result in intensive hot electron emission from the surface. This emission, in turn, leads to this charge rapid disappearing. This mechanism prevents such insulators from charging under the electron beam irradiation and facilitates processing them significantly. Main features of emission of this kind are discussed.

In present work are received high efficient and firm extruded material on the base of Bi_0.85Sb_0.15 solid solutions is obtained for low temperature coolers. Thermo and magnetothermoelectric figures of merit of developing material are sufficiently high and close to those for the monocrystalline samples, but firmness on bending in approximately 3 times exceeds firmness of monocrystalline samples. When doping samples Bi_0.85Sb_0.15 with 0,0005 at.% Te Z grows and reaches values 6,2 (DOT) 10^-3 K^-1. Magnitothermoelectrical figure of merit (Z_mte) Bi_0.85Sb_0.15 solid solutions, doped with 0,0005 at.% Te at the temperature approximately 77 K and intensity of magnetic field approximately 11 X 10⁴ A/m, has a value qual approximately 7,2 (DOT) 10^-3 K^-1. It is shown that under doping of the samples Bi_0.85Sb_0.15 by atoms with the concentration 0,05 at.% and more, changing a type of conductivity from electronic to hole occurs at temperatures below approximately 130 K, that leads to inversions of sign of factors coefficients (alpha) and R_H. Z for the samples of p-type conductivity reaches values approximately 0,84 (DOT) 10^-3 K^-1 at approximately 77 K.

The main physicochemical phenomena occurring at the interface of Bi₂Te₃-Sb₂Te₃ and Bi₂Te₃-Bi₂Se₃ crystals with Bi-, Sb-, Sn-, Pb-, Cd-, Ag-, and Ni-based metallic alloys (contact materials) are analyzed. It is shown that crystal surface damage, diffusion of the contact material into the near-contact region accompanied by changes in carrier concentration and work function, and the formation of intermediate-phase layers at the interface play a decisive role in the formation of electrical and adhesive properties of the contacts. It is demonstrated that low-resistance transition contacts with stable electrical parameters and sufficient adhesion strength can be fabricated.

The dependence of thermoelectrical efficiency Z of thermoelements based on Bi_0.5Sb_1.5Te₃ and Bi₂Te_2.7Se_0.3 on the branches materials resistivity p at different values or resistance or transitional contacts r and branches length 1; on branches length 1 at different p and r; and on transitional contacts resistance r at different p and 1 of branches have been studied. It has been found, that for given commutation alloy the length l_k, after which the strong reduction of (Delta) T_max had been observed with decreasing branches length, does not depend on branches resistivity. Although, at the transition from alloy with small contact resistance to the large ones, l_k is shifted to large branch lengths. It can be explained by the fact that for the same alloy r itself depends on crystals p; the majority charge carriers concentration in crystal is decreased with increasing p, that leads to the increase of crystal-contact alloy junction resistance. It has been found that r of contacts is directly proportional to branches p. Therefore, the ratio r/p remains r is changed under the transition from one alloy to the other, and it leads to the shifting of l_k value.

Influence of ionizing irradiation of different kinds on the thermoelectrical parameters of the thermoelements on the base of Bi₂Te₃-Bi₂Se₃ and Bi₂Te₃- Sb₂Te₃ systems solid solutions have been investigated. To ascertain the mechanism of the action of irradiation on thermoelectrical parameters of TEC, previously the influence of this irradiation on the properties of crystals also was studied. The samples investigated were obtained by the oriented crystallization method--Bridgman technique and subjected to action of gamma- irradiation in the range of fluences 10⁶ - 10⁸ R, electron irradiance of 25 MeV energy in fluence range 10¹³ - 10¹⁴ cm^-2 and pulse gamma-neutron irradiation in fluence range 10¹³ - 10¹⁴ cm^-2. It is shown that irradiation by gamma-neutrons up to fluences 10¹⁴ cm^-2 leads to increasing of (Delta) T_max of TEM, as well as efficiency of n- and p- branches of thermoelements. This fact permits to suppose, that such a variations of (Delta) T_max are due both to decreasing of resistance of transitional contacts and increasing of thermoelectric figure of merit of the thermoelectric material itself. Thus results obtained are indicated that variations of (Delta) T_max for TEM under irradiation are due both to variations of thermoelement branches parameters and the resistance of transitional contacts.

In present work study of dependencies of transional contacts r_k of extruded samples Bi₈₅Sb₁₅ solid solution with the alloy mass.%: 57Bi + 43Sn with melting temperature T_m approximately equals 412 K on the intensity of magnetic field and temperature. This contact alloy is broadly use at commutation of thermoelements on the base Bi-Sb system solid solution. At the fixing of contact on torahs of extruded samples Bi₈₅Sb₁₅ occurs a mutual diffusion of components of solid solution and contact alloy each to other. So as a result of diffusions of atoms Sn from the contact alloy in Bi₈₅Sb₁₅ solid solution near the contact appears near-contact layer of given solid solution, doped by atoms of tin. By doping near contact layer of branches of thermoelements on the base of Bi₈₅Sb₁₅ solid solution with donor impurities, compensating action of acceptor atoms, diffusing from the contact alloy in this layer, possible vastly lower r_k and raise efficiency of thermoelements.