Method of detecting electromagnetic radiation and device for realising said method

FIELD: physics.

SUBSTANCE: method involves generating reference emf via spatial separation of charges arising from irradiation of structures made of semiconductor materials and including a potential barrier and an array of quantum-size objects in the region of the barrier with radiation with particle energy in the region of fundamental absorption in structures or during injection of charge carriers through the potential barrier as a result of irradiation of such structures with radiation with particle energy sufficient for injection of charge carriers, irradiation of quantum-size objects with detectable electromagnetic radiation, recording change in emf when the structures are irradiated with detectable electromagnetic radiation. Said result is achieved due to that the device has structures made of semiconductor materials having a potential barrier in the region of which an array of quantum-size objects is formed, a reference radiation source for irradiating structures in order to generate reference emf and a device which detects change in emf when the device is irradiated with detectable electromagnetic radiation.

EFFECT: high sensitivity and providing optical control of characteristics of a photovoltaic detector, particularly dynamic range and sensitivity.

14 cl, 6 ex, 3 dwg

 

The inventive method and device related to Photonics, in particular for photovoltaic devices suitable for use as detectors of electromagnetic radiation in a wide wavelength range in the device to form the image, the coordinates of the studied objects, optical measurements, automatic control, monitoring and measurement of radiation, environmental monitoring, medical diagnostics and nondestructive testing.

There is a method of energy conversion of electromagnetic radiation into electrical energy through solar cells (EN 2222846 [1]), which contains located on a metal plate semiconductor layers of n - and p-type with a p-n junction between them and the transparent conductive layer. In the layer of n-type semiconductor added metal nanoparticles with a size much smaller than the wavelength of the radiation, at a concentration of these nanoparticles in the specified layer (1-5)·10-2volume fractions. The result is improved efficiency of the device.

The disadvantages of this device include the lack of ability to control the functional characteristics of the solar cell, in particular photosensitivity. In addition, the known method is unsuitable for the inventive device for detecting E. ectromagnetic radiation.

A known method of controlling the photosensitivity of the sensor (detector) laser radiation by means of external fields. The sensor (detector) is based on fully depleted alloy superlattice GaAs, covering the entire range from 0.8 to 1.4 μm (Y. Horikoshi, the Rivne regional oncologic dispensary K. Appl. Phys. A. - 1985, v.37, R; Herman M. "Semiconductor superlattices". Publishing house "Mir", 1989, s [2]). The photoexcited electrons and holes immediately after birth are separated field alloy superlattice, which leads to a high quantum efficiency of the device. Due to the complete depletion of alloy superlattice behaves like a very high resistance material to be applied along the layers in a strong electric field using selective p+- R+-transitions. The sensitivity of the instrument at the wavelength of 1.3 μm is 90% of the original interband the photoresponse with a 0.85 μm, and the external quantum yield at a 0.85 μm reaches 65%. This high photosensitivity is a very large value of the electric field, consisting of the internal field of the space charge and external applied electric field.

However, the application of a high electric field leads to an increase in leakage currents, noise and electrical breakdown of the semiconductor layers of the superlattice. In addition, the known method is unsuitable the La inventive device for detecting electromagnetic radiation.

Closest to the claimed by its technical essence is a known method of controlling the photosensitivity of the detector of the laser radiation in the infrared range (EN 2418344 [3]). The method is designed for a detector made of a quantum wire based on InSb and doped with donor impurity type, and provides the effect on the detector external fields.

The diameter of the quantum wire is approximately equal to the magnitude of the effective Borowski radius for an electron in the material of the quantum wire, and as the external effects of using a magnetic field of from 2 to 5 Tesla.

However, the known method is unsuitable for the inventive device for detecting electromagnetic radiation.

A known sensor based on doped compensated semiconductor, in which one of the two contacts made in the form of two or more items placed from one another at a distance that ensures the closure of areas of the space charge. While in the operating mode between the elements of current flow driven non-stationary charge in the semiconductor volume, which leads to an increase of the ratio of the photoelectric gain while maintaining a significant quantum efficiency (SU 1816166 [4]).

A disadvantage of the known device is its relatively low sensitivity.

<> Known photo-detectors, sensitive in the middle range of infrared radiation and having a selective (or close to it) spectral response.

For example, such as Ge, doped Zn, ti or Nd, or detectors based on solid solutions Cd×Hg1-xTe (RU 2310949 [5]), which have high sensitivity with maximum at λ=4,5 µm, but require deep cooling or have limited temporal resolution.

The disadvantage of these detectors is the complexity of the integration process of their manufacture in standard monolithic silicon technology.

Known photodetector based semiconductor structures with quantum wells, comprising a substrate of semi-insulating GaAs buffer layer, an i-GaAs first contact layer of n-GaAs, a system of alternating layers of Al×Ga1-xAs and GaAs, and in one of the materials system of alternating layers of introduced impurity silicon to the doping level of 2·1018cm-3and the second contact layer n-GaAs (B.F. Levine et al, Electe. Zett. 1988, v.24, p.747-749 [6]). The mole fraction of Al (x) in the triple connection is constant and equal to 0.31 in. The doping level of Si in GaAs is 2·1018cm-3. Superlattice contains 50 layers each connection (the periodicity of the lattice is equal to 50). Layers of GaAs separated by layers of wide bandgap Al×Ga1-xAs. E-the condition εnin GaAs localized in the quantum is the pits. The energy levels of Si in the adjacent GaAs layers do not overlap due to the large thickness of the Al×Ga1-xAs. At the border of layers of GaAs and Al×Ga1-xAs occurs heterojunctions.

A system of alternating layers with a large difference between their thicknesses can be characterized as "structure with spaced superlattice" unlike conventional superlattice, where adjacent layers have comparable thickness.

Known photodetector operates as follows. Radiation with energy ε=hω equal to the value of the energy gap between the levels of n in GaAs quantum well and the zone of the free States, provides a transition I of the electrons in this area, and if you have an external pull field E (causing the slope of the band energy diagram) there is an effect of photoconductivity, the value of ΔG is determined by the expression ΔG=Δnev, where Δn is the concentration of photoexcited electrons; v - velocity; e is the electron charge.

Known photodetector has the following disadvantages.

In the state of thermodynamic equilibrium, the electrons are redistributed between the impurity levels of silicon Si and level n in a potential well in GaAs. Thermal excitation of electrons from the level of Si at level εn(process II) and their reverse recombination (process III) cause the level εnis not fully populated. Recent circumstances shall elsto limits the quantum yield and reduces the effect of photoconductivity, as not all of the electrons are excited quanta hω (process I) in the free zone.

Another disadvantage of the known photodetector is the presence of dark current (with jump) on impurity States (process III).

The disadvantage of this detector is the complexity of the integration process of its manufacture in standard monolithic silicon technology.

In addition, this detector is in contrast to the claimed device is designed to operate in mode photoshoprecovery, i.e. it measures the change in the value of the photocurrent under the action of a registered radiation, and not changing EMF, and is not intended for registration of radiation in photovoltaic mode.

The closest technical solution to the stated photodetector is based on semiconductor structures with quantum wells comprising a substrate of semi-insulating GaAs buffer layer, an i-GaAs first contact layer of n-GaAs, a system of alternating layers of Al×Ga1-xAs and GaAs, and in one of the materials system of alternating layers of introduced impurity silicon to the doping level of 2·1018cm-3and a second contact layer of n-GaAs. When the silicon is introduced into the layer of Al×Ga1-xAs in the form of a monatomic layer, located at a distance not larger Debye length shielded from one of the alternate interfaces the s layers (EN 2022411 [7]).

The disadvantage of this detector is the complexity of the integration process of its manufacture in standard monolithic silicon technology. In addition, detectors of this type are designed to operate only in the mode photoshoprecovery and are not designed to detect radiation in photovoltaic mode.

The inventive method and device for detecting electromagnetic radiation directed at improving the sensitivity and providing optical control characteristics of a photovoltaic detector, in particular, dynamic range and sensitivity.

This result in part of the method is achieved in that the method involves the creation of strong EMF due to the spatial separation of charges arising from the irradiation of the structures formed on the basis of semiconductor materials and includes a potential barrier and an array of quantum-dimensional objects in the field of barrier-rays with the energy of the particles in the region of fundamental absorption in structures or during the injection of charge carriers through the potential barrier due to the irradiation of such structures radiation with an energy of particles, sufficient for injection of charge carriers, irradiation of quantum-dimensional objects detektivami electromagnetic radiation, registration changes EMF when irradiation of the attachment structure detektivami electromagnetic radiation.

This result in part of the device is achieved by the fact that it contains formed on the basis of semiconductor materials structure with a potential barrier, which created an array of quantum-dimensional objects, the source of reference radiation for irradiation patterns to create the reference EMF and device for registering the change in EMF irradiation device detektivami electromagnetic radiation.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form of a p-n junction.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form of a p-i-n junction.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form R-R+transition.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form of n-n+transition.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form of a Schottky barrier.

This result in part of the device is achieved by the fact that the region of the potential barrier is made in the form of a heterojunction.

This result in part of the device is achieved by the fact that toobest potential barrier is made in the form of a combination of barriers.

This result in part of the device is achieved by the fact that the quantum-dimensional objects are quantum dots.

This result in part of the device is achieved by the fact that the quantum-dimensional objects represent the quantum well.

This result in part of the device is achieved by the fact that the quantum-dimensional objects are quantum threads.

This result in part of the device is achieved by the fact that the quantum-dimensional objects are quantum rings.

This result in part of the device is achieved by the fact that the array of quantum-dimensional objects consists of a combination of quantum-dimensional objects.

Create the EMF due to the spatial separation of charges allows you to get registered physical quantity (EMF), which changes due to the impact of detected radiation to an array of quantum-dimensional objects provides a device functioning as intended.

Irradiation of structures formed on the basis of semiconductor materials and includes a potential barrier and an array of quantum-dimensional objects in the field of barrier-rays with the energy of the particles in the region of fundamental absorption in structures allows you to create reference EMF; the use of radiation with the energy of the th particle in the region of fundamental absorption in structures provides the necessary photoelectric conversion efficiency (quantum yield of the internal photoelectric effect).

The use of injection of charge carriers through the potential barrier due to the irradiation of such structures radiation with an energy of particles, sufficient for injection of charge carriers, provides an alternative way to create the reference EMF, providing the necessary efficiency (quantum yield) of the photoelectric conversion.

Irradiation of quantum-dimensional objects detektivami (registered) electromagnetic radiation leads to a change in the charge state of the quantum-dimensional objects and, as a consequence, depending on the type of quantum-dimensional objects and energy patterns of the potential barrier increases or decreases the efficiency of photoelectric conversion of the reference radiation and, consequently, increases or decreases the value of the reference EMF (EMF arising on the structure due to its exposure to the reference radiation), which allows to detect the recorded electromagnetic radiation.

To change the reference EMF due to EMF exposure arising on the structure due to its exposure to a reference radiation patterns detektivami (registered) electromagnetic radiation is a useful signal of the device.

The formation on the basis of the semiconductor structure with the potential barrier and the establishment of a region of the array of quantum-size the data objects through the photovoltaic effect to create the reference EMF and to detect the recorded electromagnetic radiation due to the change under the influence charge quantum-dimensional objects, change

as a consequence, the efficiency of photoelectric conversion and the magnitude of the EMF.

The source of reference radiation for irradiation region of the potential barrier is necessary to create a reference EMF and device for registering the change in EMF irradiation device detektivami electromagnetic radiation, for reception of the useful signal, in particular, display systems, visualization, measurement.

The potential barrier can be made of almost any selected from among known. Each of them has its advantages.

For example, when the potential barrier is made in the form of a p-n junction, with the necessary efficiency of the photoelectric conversion region of the p-n junction can be made compact.

When performing the field potential barrier in the form of a p-i-n junction may have more precise control range of the photosensitivity of the detector through the accurate positioning of the array of quantum-dimensional objects in the area of self-field patterns. In addition, by increasing the thickness of the i-region of the structure can increase the number of layers and total thickness of multilayer arrays of quantum-dimensional objects embedded in its own structure.

If the potential barrier region is made in the form R-R+/sup> transition, it is possible to create a unipolar barriers p-type ohmic contact to the p+-region. If the potential barrier region is made in the form of n-n+transition, it is possible to create a unipolar barriers n-type ohmic contact to n+-region. The combination of barriers of this type allows you to create a structure of type n+-n-R-p+and simplifies the creation of ohmic contacts to the anode and to the cathode region of the detector.

If the potential barrier region is made in the form of a Schottky barrier, it is possible to improve performance and radiation resistance of the detector.

If the potential barrier region is made in the form of a heterojunction, it is possible to control the spectral (energy) characteristics of radiation used to create the reference EMF, and selection of optimal design solutions of the radiation source to generate the reference EMF.

When performing the field potential barrier in the form of a combination of barriers it is possible to control the electrophysical and photoelectric characteristics and topological structure of the detector, in particular when used as part of the integrated circuit.

If quantum objects are quantum dots, it is possible to create detectors with the same feeling what eTelestia to radiation of any polarization and construction of detectors with a predetermined and variable in a wide range of spectral characteristics.

If quantum-dimensional objects are quantum wells, it is possible to create multi-band detectors.

If quantum-dimensional objects represent a quantum filament, it is possible by arranging them along the chosen direction in the crystal to create detectors that are sensitive to the polarization direction of the detected radiation.

If quantum-dimensional objects are quantum rings, it is possible detection of electromagnetic radiation not only in the infrared wavelength range, but, as follows from the calculation of the energy spectrum and the distribution of charge density of hole States localized on quantum rings SiGe embedded in the matrix Si (Kuchinsky P.A., Zinoviev V.A., A.V. Nenashev, Armbrister V.A., V.A. Volodin, dvurechensky AV // Quantum rings SiGe on Si(100)surface". Materials of electronic engineering. - 2011, №4 [9]), in the submillimeter region of the spectrum.

If the array of quantum-dimensional objects consists of a combination of quantum-dimensional objects, it is possible as the design of detectors, combining the previously specified properties inherent in certain quantum-dimensional objects, and giving detector is am new qualities, resulting from the interaction of nanostructures with each other.

The essence of the proposed method and device for detecting electromagnetic radiation are illustrated by examples of implementation and graphic materials. Figure 1 shows the block diagram of the device for the detection of electromagnetic radiation. Figure 2 schematically presents a cross-section of the actual detector, part of the detection device of electromagnetic radiation. Figure 3 presents the dependence of the detecting ability of the infrared detector based on silicon p-n junction with a set of layers of quantum dots Germany on the extent of the devastation array of quantum dots.

Example 1.

A device for detecting electromagnetic radiation contains formed on the basis of semiconductor materials structure 1 (the detector) with a potential barrier, which created an array of quantum-dimensional objects, source 2 reference radiation for irradiation patterns to create the reference EMF and the device 3, registration change EMF irradiation device detektivami electromagnetic radiation 4 from the source 5. Source 2 reference radiation for irradiation region of the potential barrier can be used any source suitable for this celinedion, as the reference radiation can be applied radiation of a semiconductor laser or led, or surface plasmon-polariton supplied to the region of the potential barrier along the waveguide. As unit 3, registration change EMF irradiation device detektivami electromagnetic radiation, also selected any device suitable for this purpose. For example, in multi-element or matrix detectors can be applied to a CMOS readout circuit (multiplexer), which is a modification of the sense applied to the signal in the silicon photodetector matrices, while in a single-element detectors can be used suitable for the characteristics of the voltmeter.

For example, the authors for the reception of the signal from a single-element detector was used selective nanovoltmeter.

Detector (formed on the basis of semiconductor materials structure) was made as follows: method UHV molecular beam epitaxy was formed semiconductor structure 6, containing the potential barrier region 7 has an inbuilt multi-layered array of quantum-dimensional objects 8. Photodetecting sites detector formed by photolithography and chemical etching. Ohmic contacts to polypr vodnikova structure was formed by thermal or plasma spraying in different directions from the region of the potential barrier (not shown).

A device for detecting electromagnetic radiation with the implementation of the method of detecting electromagnetic radiation operates as follows.

As an example, consider the generated infrared detector 1 on the basis of silicon p-n junction formed on the substrate Si(001), in the space charge region which is in the plane (001) - grown set of layers (dense two-dimensional arrays of quantum dots of Ge with a certain effective thickness of each layer deposited Germany, separated by layers of silicon with a thickness, excluding the interaction of layers of quantum dots of Ge among themselves. The reference voltage in such a structure was created by laser radiation from the source 2 quantum energy in the region of fundamental absorption of Si, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF occurred because of a change in charge state of germanium array of points due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 2-5 microns, corresponding to the energy structure of the formed Ge quantum dots in silicon. The spectral range of such a detector to a certain extent depends on the type and geometrical parameters of the GE quantum dots, layer density (which is allocated by the growth conditions and monitored by scanning tunneling microscopy), the number of layers and the operating temperature of the detector.

Example 2.

The implementation of the invention was carried out analogously to example 1, but as a potential barrier was used silicon p-i-n junction, in its own area which formed a set of layers (two-dimensional arrays) parallel quantum wires SiGe, ordered in all layers along the same crystallographic direction, separated by layers of silicon with a certain thickness, excluding the interaction of the layers of SiGe quantum wires between them. The reference voltage in such a structure was created by the emitted light (source 2) quantum energy in the region of fundamental absorption of Si, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF was due to the change of the charge state of the array of quantum wires due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 1.5 to 5 μm, corresponding to the energy structure of the formed SiGe quantum wires in silicon. The spectral range of such a detector depends on the geometrical parameters of the quantum wires, their composition (the ratio between the content of Si and Ge), layer density (as determined by the growth conditions and is controlled by scanning tunneling is microscopy), the number of layers and the operating temperature of the detector. A distinctive feature of such a detector is the strong dependence of its spectral sensitivity of the angle between the direction in which lay a quantum filament, and the plane of polarization of the detected radiation.

Example 3.

The implementation of the invention was carried out analogously to example 1, but as a potential barrier was used silicon p-R+transition, in the space charge region which is formed a set of layers (two-dimensional arrays) quantum rings SiGe, separated by layers of silicon with a certain thickness, excluding the interaction layers of quantum rings SiGe each other. The reference voltage in such a structure was created by the emitted light (source 2) quantum energy in the region of fundamental absorption of Si, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF was due to the change of the charge state of the array of quantum rings due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 1.5 to 4 μm, corresponding to the energy structure of the formed quantum rings in SiGe silicon. The spectral range of such a detector depends on the geometrical parameters of quantum rings, their chemistry is ical composition (the ratio between the content of Si and Ge), layer density (as determined by the growth conditions and is controlled by scanning tunneling microscopy), the number of layers and the operating temperature of the detector. A distinctive feature of such a detector is theoretically predicted the possibility of detecting electromagnetic radiation not only in the infrared wavelength range, but as follows from the calculation of the energy spectrum and the distribution of charge density of hole States localized on quantum rings SiGe embedded in the matrix Si (Kuchinsky P.A., Zinoviev V.A., A.V. Nenashev, Armbrister V.A., V.A. Volodin, dvurechensky AV // Quantum rings SiGe on Si(100)surface". - Electronic materials. - 2011, №4 [9]), in the submillimeter region of the spectrum.

Example 4.

The implementation of the invention was carried out analogously to example 1, but as a potential barrier was used p-i-n heterojunction p-Si×Ge1-x/i-Siy(z)Ge1-y(z)/n-Si(001) (a combination of p-i-n junction and heterojunction) with smooth change Ge content y(z) from 0 to x in own region (i-region) heterostructures, in which a set of layers (two-dimensional arrays of quantum dots of Ge with a certain effective thickness of each layer deposited Germany, separated by layers of silicon with a thickness of providing interaction of the layers quantificacao Ge between themselves and the interlayer ordering of Ge quantum dots. The reference voltage in such a structure was created by radiation from a tungsten lamp with an infrared filter (source 2) quantum energy in the region of fundamental absorption of SiGe, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF occurred because of a change in charge state of germanium array of points due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 2.5-5 µm, the corresponding energy array structure formed of quantum dots of Ge in transition (graded-gap layer of SiGe. The spectral range of such a detector depends on the type and geometrical parameters of the GE quantum dots, layer density (as determined by the growth conditions and is controlled by scanning tunneling microscopy), the number of layers of quantum dots of Ge, the thickness of the barrier layers of Si and the operating temperature of the detector and on the composition of the transition (graded-gap layer of SiGe. One distinguishing feature of this detector is that as the reference radiation can be used radiation with quantum energy in the region of fundamental absorption of SiGe having a long wave in comparison with the emission of energy quanta in the field of fundamental absorption of Si.

P is the iMER 5.

The implementation of the invention was carried out analogously to example 1, but as a potential barrier was used silicon n-n+the transition in combination with the Schottky barrier Pt/n-Si in the space charge region which is formed by a set of quantum wells n-SiGe doped with phosphorus, separated by layers of silicon with a certain thickness, excluding the interaction SiGe quantum wells between them. The reference voltage in such a structure was created by the emitted light (source 2) quantum energy in the field of fundamental Si absorption or radiation of longer wavelengths of the laser that provides the injection of carriers through the barrier Schottky Pt/n-Si n-region structure, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF was due to the change of the charge state of the quantum wells due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 2.5-4 µm, corresponding to the energy structure of the formed SiGe quantum wells in si. The spectral range of such a detector depends on the geometrical parameters of quantum wells, their chemical composition (the ratio between the content of Si and Ge), the number of layers and the operating temperature of the detector. One distinguishing feature of this detector is one the Xia, for example, high radiation resistance.

Example 6.

The implementation of the invention was carried out analogously to example 1, but as a potential barrier was used silicon p+-R-n-n+-the transition (any combination of transitions p-p+and n-n+), in the space charge region which is formed by a set of quantum wells p-SiGe, doped with boron, separated by layers of silicon with a certain thickness, excluding the interaction SiGe quantum wells between them. The reference voltage in such a structure was created by the emitted light (source 2) quantum energy in the region of fundamental absorption of Si, and in principle, can be created in any (not necessarily electromagnetic radiation with sufficient energy particles. To change the reference EMF was due to the change of the charge state of the quantum wells due to exposure to infrared radiation 4 from source 5 with a wavelength in the range of 2-4,5 μm, corresponding to the energy structure of the formed SiGe quantum wells in si. The spectral range of such a detector depends on the geometrical parameters of quantum wells, their chemical composition (the ratio between the content of Si and Ge), the number of layers and the operating temperature of the detector. A distinctive feature of such a detector is the ease of formation of ohmic contacts to both is alucam diode.

1. The method of detecting electromagnetic radiation using structures formed on the basis of semiconductor materials, with the potential barrier and the array of quantum-dimensional objects in the field of the barrier, including the creation of strong EMF due to the spatial separation of charges arising from the irradiation of such structures radiation with an energy of particles in the region of fundamental absorption in structures or during the injection of charge carriers through the potential barrier due to the irradiation of such structures radiation with an energy of particles, sufficient for injection of charge carriers, irradiation of quantum-dimensional objects detektivami electromagnetic radiation and registration changes EMF irradiation patterns detektivami electromagnetic radiation.

2. A device for detecting electromagnetic radiation containing formed on the basis of semiconductor materials structure with a potential barrier, which created an array of quantum-dimensional objects, the source of reference radiation for irradiation patterns to create the reference EMF and device for registering the change in EMF irradiation device, detektivami electromagnetic radiation.

3. The device according to claim 2, characterized in that the region of the potential barrier is made in the form of a p-n junction.

4. Device is istwo according to claim 2, characterized in that the region of the potential barrier is made in the form of a p-i-n junction.

5. The device according to claim 2, characterized in that the region of the potential barrier is made in the form R-R+transition.

6. The device according to claim 2, characterized in that the region of the potential barrier is made in the form of n-n+transition.

7. The device according to claim 2, characterized in that the region of the potential barrier is made in the form of a Schottky barrier.

8. The device according to claim 2, characterized in that the region of the potential barrier is made in the form of a heterojunction.

9. The device according to claim 2, characterized in that the region of the potential barrier is made in the form of a combination of barriers.

10. The device according to claim 2, characterized in that the quantum-dimensional objects are quantum dots.

11. The device according to claim 2, characterized in that the quantum-dimensional objects represent the quantum well.

YoY according to claim 2, characterized in that the quantum-dimensional objects are quantum threads.

13. The device according to claim 2, characterized in that the quantum-dimensional objects are quantum rings.

14. The device according to claim 2, characterized in that the array of quantum-dimensional objects consists of a combination of quantum-dimensional objects.



 

Same patents:

FIELD: physics.

SUBSTANCE: inventions can be used in threshold photodetectors for detecting weak electromagnetic radiation in the infrared range. The high signal-to-noise ratio infrared photodiode has a heavily doped layer adjacent to a substrate which is transparent for infrared radiation, whose thickness l1 satisfies the condition: and a weakly doped layer of another conductivity type (base), whose thickness d satisfies the condition d<L. Ohmic contacts are formed along two opposite sides of the periphery of the weakly doped layer. To increase the signal-to-noise ratio in the infrared photodiode, the sum of diffusion current and photocurrent of the p-n junction, and current of the longitudinal conductance of the base, which flows between ohmic contacts formed along two opposite sides of the periphery of the weakly doped layer, is determined, while applying a small voltage across said contacts, which satisfies a given condition.

EFFECT: invention increases the signal-to-noise ratio of the infrared photodiode by using current of longitudinal conductance of the base, whose noise is correlated with noise of the diffusion current of the p-n junction, for correlated processing of the signal and the noise of the p-n junction which detects infrared radiation.

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EFFECT: high signal-to-noise ratio of the infrared photodiode.

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EFFECT: disclosed method enables to increase the signal-to-noise ratio of the photodiode in the high frequency range by reducing spectral range of diffusion current fluctuation.

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EFFECT: possibility of making a highly stable infrared sensitive structure with broad functional capabilities.

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EFFECT: increased sensitivity of the end product.

2 cl, 2 dwg, 1 tbl

FIELD: physics, photography.

SUBSTANCE: invention can be used, for instance in wide-field heat direction finding or thermal imaging devices working in two spectrum regions. The dual spectrum photodetector consists of p modules, each having photosensitive elements, two multiple-element photosensitive lines, a multiplexer and a base. The first multiple-element line is sensitive in one spectrum region and lies on the substrate of the first photosensitive element and the second multiple-element line is sensitive in the other spectrum region and lies on the substrate of the second photosensitive element. In one version first photosensitive elements are trapezium shaped, which enables to arrange the modules such that photosensitive structures, each formed by the lines which are sensitive in one spectrum region, have the shape of regular polygons. In the other version second photosensitive elements are rectangular shaped, which enables arrangement of the modules such that photosensitive structures are in form of a line.

EFFECT: design of dual spectrum large-format multiple-module photosensitive structures of different configurations.

8 cl, 6 dwg

FIELD: power engineering.

SUBSTANCE: invention is used in optical data acquisition systems with high registration efficiency of light radiation by means of avalanche photodiodes with Geiger discharge quenching circuit. Into solid Geiger detector with active restorer, which includes avalanche photodiode the anode whereof is connected to the shift voltage bus and cathode is connected to the first electrode of damping resistor, and a switching restoring transistor, there introduced is the additional damping resistor. The first electrode of the additional damping resistor is connected to the second electrode of damping resistor and to the sink of switching restoring transistor the gate of which is connected to the first electrode of damping resistor, and sink is connected to the second electrode of the additional damping resistor and detector power bus. Switching restoring transistor is made in the form of transistor with a built-in channel.

EFFECT: increasing dynamic range of detector as well as increasing registration efficiency.

1 dwg

FIELD: infrared detectors.

SUBSTANCE: proposed photodiode infrared detector has semiconductor substrate translucent for spectral photodetection region rays and semiconductor graded band-gap structure disposed on substrate;. graded band-gap structure has following layers disposed one on top of other on substrate end. Highly conductive layer of one polarity of conductivity and fixed forbidden gap width produced by heavy doping; layer of other polarity of conductivity and other forbidden gap width in the form of little hump whose value gradually rises from that corresponding to forbidden gap width of preceding layer and then, with smoother decrease to value corresponding to forbidden gap width of preceding layer or smaller. Working layer of same polarity of conductivity as that of preceding layer and fixed forbidden gap width equal to degree of final decrease in forbidden gap width of preceding layer and also equal to forbidden gap width in first of mentioned layer or smaller. Working layer is provided with p-n junction exposed at its surface. Layer disposed on working-layer p-n junction and having gradually increasing forbidden gap width to value corresponding to working layer and polarity of conductivity reverse to that of working layer.

EFFECT: maximized current-power sensitivity, enhanced maximal photodetection frequency, uniform parameters with respect to surface area.

12 cl, 2 dwg

FIELD: fiber-optic communications, data protection, telecommunications, large-scale integrated circuit diagnosing and testing, single molecule spectrometry, astronomy, and medicine.

SUBSTANCE: proposed device has substrate carrying contact pads, One strip is made of superconductor in the form of meander and its ends are connected to contact pads. Other, additional, semiconductor strip is connected in parallel with above-mentioned strip made in the form of meander. Additional strip is made of superconductor whose kinetic inductance is lower than that of strip made in the form of meander.

EFFECT: enhanced speed, sensitivity, and bandwidth of detector.

9 cl, 2 dwg

FIELD: spectral-analytical, pyrometric and thermal-vision equipment.

SUBSTANCE: emitter has electro-luminescent diode of gallium arsenide, generating primary emission in wave length range 0,8-0,9 mcm, and also poly-crystal layer of lead selenide, absorbing primary emission and secondarily emitting in wave length range 2-5 mcm, and lead selenide includes additionally: admixture, directionally changing emission maximum wave length position as well as time of increase and decrease of emission pulse, and admixture, increasing power of emission. Photo-element includes lead selenide layer on dielectric substrate with potential barrier formed therein, and includes admixtures, analogical to those added to lead selenide of emitter. Optron uses emitter and photo-elements. Concentration of addition of cadmium selenide in poly-crystal layer of emitter is 3,5-4,5 times greater, than in photo-element. Open optical channel of Optron is best made with possible filling by gas or liquid, and for optimal synchronization and compactness emitter and/or photo-element can be improved by narrowband optical interference filters.

EFFECT: higher efficiency, broader functional capabilities.

3 cl, 3 tbl, 6 dwg

FIELD: physics.

SUBSTANCE: in a solid-state image capturing device, a photoelectric conversion portion, a change retention portion, a transfer portion and a reading unit are formed in a p-type pocket. The charge retention portion is configured to include an n-type semiconductor region which is a first semiconductor region which holds charges in a portion different from the photoelectric conversion portion. A p-type semiconductor region, having a higher concentration than the p-type pocket, is situated under the n-type semiconductor region.

EFFECT: enabling charge transfer at low voltage, first by preventing expansion of the depletion layer during transfer of charges from the charge retention portion to a floating diffusion region and, secondly, by preventing narrowing of the transfer channel between the charge retention portion and the floating diffusion region.

33 cl, 13 dwg

FIELD: physics.

SUBSTANCE: image-forming apparatus includes an array of sub-diffraction limit-sized light receptors formed in a substrate having a light receiving surface. Each light receptor is configured to output a scalar valued multi-bit element and change state based on absorption of at least one photon. The apparatus further includes an optical filter system disposed over the light receiving surface, the optical filter system having an array of filter pixels each having an associated pass-band spectral characteristic. A data element obtained from the array of sub-diffraction limit-sized light receptors includes a combination of a plurality of the multi-bit elements output from a plurality of light receptors that underlie filter pixels having at least two different pass-band spectral characteristics.

EFFECT: high optical sensor sensitivity and improved colour accuracy.

20 cl, 11 dwg

FIELD: physics.

SUBSTANCE: solid-state image sensor includes a first semiconductor region of a first conductivity type, a second semiconductor region of a second conductivity type in contact with the bottom surface of the first semiconductor region and operating as a charge accumulation region, a third semiconductor region, which includes side surfaces surrounded by the second semiconductor region, a fourth semiconductor region of a second conductivity type, situated away from the second semiconductor region, and a transfer gate which forms a channel for transferring charges accumulated in the second semiconductor region into the fourth semiconductor region. The third semiconductor region is a region of a first conductivity type or second conductivity type, and concentration of impurities therein is less than that in the second semiconductor region. The third semiconductor region has a top surface in contact with the second semiconductor region.

EFFECT: meeting requirements for the number of charges in saturation state, operating parameters for transfer and sensitivity of the disclosed image sensor.

3 cl, 9 dwg

X-ray detector // 2498460

FIELD: physics.

SUBSTANCE: working volume of the detector is made from a plate of semi-insulating monocrystalline semiconductor material, e.g., gallium arsenide, on which capacitors are formed, the first plate of the capacitors lying directly on the working volume. The top of the capacitors is coated with a layer of a separating dielectric, and electronic switches based on field-effect transistors are formed on the layer of the separating dielectric on which is also formed the whole layout of circuits, including buses which connect transistor gates (located on the separating dielectric) along the rows of a matrix, as well as buses which connect transistor drains along columns, wherein windows are formed in the dielectric layer, the windows being filled with metal and the first capacitor plates are connected to transistor sources and second capacitor plates are connected to ground buses in each matrix element through said windows.

EFFECT: widening the range of semiconductor materials suitable for use as the working volume of the detector.

1 dwg

FIELD: physics.

SUBSTANCE: device has m reading channels. Each reading channel consists of a reading unit with n reading cells, a block of signal time delay and accumulation (TDA) stages with n signal TDA stages and is provided with a k-bit shift register, where k is the number of bits of a distributed analogue-to-digital converter. The reading unit is connected by an N-bit voltage comparison signal bus with the block of TDA stages. Each reading cell is connected to the corresponding N-th bit of the N-bit voltage comparison signal bus. The reading cell comprises an integrating amplifier, a sampling and storage cell, a comparator, a latch and a logic AND element. Analogue elements - integrating amplifier, sampling and storage cell and comparator - are connected in series in said order relative one of the inputs of each by analogue buses. The integrating amplifier is connected to a photodetector. A TDA stage comprises a parametric comparison signal multiplexer, a logic AND element, a k-bit counter, a k-bit element with three states at the output, connected in series in said order, as well as an additional k-bit shift register. One of the N-bit inputs of the parametric multiplexer is connected to an N-bit voltage comparison signal bus. The output of the k-bit element, which is the output of the TDA stage, is connected by a K-bit bus for reading data from the reading channel to the k-bit shift register of the reading channel. The output of the k-bit shift register of each reading channel is connected by the data transmission bus of shift registers of the reading channel in the direction of the increasing number of the reading channel with the k-bit shift register of the next reading channel. The output of the m-th reading channel is connected to the output data bus of the device.

EFFECT: wider dynamic range and enabling signal reading by each channel with an unlimited number of photosensitive elements of the photodetector.

7 cl, 5 dwg

FIELD: physics.

SUBSTANCE: photoelectric conversion element for making a light path to said photoelectric conversion portion includes a middle portion and a peripheral portion having a refraction index different from that of the middle portion, within a certain plane parallel to the light-receiving surface of the photoelectric conversion portion, and within another plane lying closer to the light-receiving surface than said certain plane, and parallel to the light-receiving surface, wherein the peripheral portion is continuous with the middle portion and surrounds the middle portion; the refraction index of the peripheral portion is greater than that of the insulating film and the thickness of the peripheral portion within said other plane is smaller than that of the peripheral portion within said certain plane.

EFFECT: high sensitivity of photoelectric conversion elements with high efficiency of using incident light.

28 cl, 11 dwg

FIELD: physics.

SUBSTANCE: method of making a solid-state image capturing device which includes a substrate, having a photoelectric conversion unit, and a waveguide assembled on the substrate, wherein the waveguide matches the photoelectric conversion unit and includes a core and cladding, the method comprising a first step and a second step, where at the first step and second step an element to be moulded into a core is formed in an opening in the cladding by high-density plasma-chemical vapour deposition, wherein at the second step the element to be moulded into a core is formed by high-density plasma-chemical vapour deposition under conditions where the ratio of radio-frequency power on the side of the back surface of the substrate to the radio-frequency power on the side of the front surface of the substrate is greater than the ratio at the first step.

EFFECT: high adhesion of the built-in element and avoiding deformation in the structure.

15 cl, 15 dwg

FIELD: information technology.

SUBSTANCE: imaging device includes a pixel unit, a transistor amplifier and a control unit. The pixel unit includes a first photoelectric conversion unit which generates a first charge based on incident light of a first colour, a second photoelectric conversion unit which generates a second charge based on incident light of a first colour and a third photoelectric conversion unit which generates a third charge based on incident light of a second colour. The transistor amplifier is common for the first to third photoelectric conversion units and outputs a signal based on the first, second and third charges generated by the first, second and third photoelectric conversion units, respectively. The control unit sets the pixel unit to a selected state or an unselected state according to the electric potential of the control terminal of the transistor amplifier.

EFFECT: high image quality.

13 cl, 8 dwg

FIELD: physics.

SUBSTANCE: microbolometer is made in a framework in form of a heat-insulated portion of an active semiconductor layer supported on heat-insulating beams over an etched cavity, said portion having and being in thermal contact with an absorbing element heated by absorbed radiation, and a heat-sensitive element of an electrical circuit located outside the heat-insulated portion, connected to it by conductors which pass on the beams, the beams being double-layered with layers that are separated by a heat-insulating gap. Methods of making a microbolometer with reinforced supporting beams are disclosed.

EFFECT: design of a structure and technology of making a cheap microbolometer with thin but reinforced supporting beams.

3 cl, 3 dwg

FIELD: electricity.

SUBSTANCE: solid-state image sensor includes a charge accumulation region having a first conductivity type, a semiconductor insulating region formed from a semiconductor impurity region having a second conductivity type, a channel limiting region formed from a semiconductor impurity region having a second conductivity type, which is located on the semiconductor insulating region, and an insulator lying on the channel limiting region. The insulator has a first insulating area lying over the semiconductor insulating region through the channel limiting region, a second insulating area lying next to the outer surface of the first insulating area, wherein thickness of the second insulating area drops as distance from the first insulating area increases, and a third insulating area formed on the first insulating area, wherein the third insulating area has a top surface and a lateral surface, the lateral surface connecting the top surface of the third insulating area with the top surface of the second insulating area.

EFFECT: invention provides a method which is efficient in increasing the amount of charge in saturated state, weakens concentration of the electric field near the insulating element of the area and reducing etching damage on the substrate.

19 cl, 4 dwg

FIELD: information service technical aids.

SUBSTANCE: contact-free integrated circuit has to be functional analog of contact-free data descriptor working at different frequencies. The descriptors are used in software of electronic data turnover and for data protection. Peripheral part of contact-free integrated circuit that is used for contact-free communication with peripheral equipment through electromagnet radiation of central part. Peripheral equipment is responsible for data supply, data input and output according to preset protocol. Peripheral equipment has at least one photovoltaic semiconductor structure to transform incident electromagnet radiation of optical range to electric energy. The structure is connected to central part of contact-free integrated circuit at the side where power and data are applied. At the side of data output there are at least two voltage-controlled optically active structures to modulate reflected light radiation. Data exchange protocol corresponds to at least single-time scanning of photovoltaic and optically active structures by focused and modulated light beam. The structures are disposed on the path of the beam. Then radiation after being reflected by photovoltaic and optically active structures is subject to detection. Semiconductor laser of peripheral equipment can be used as light source.

EFFECT: improved design of disk drives.

4 cl, 1 dwg

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