Method of making gaas-based photocell

FIELD: chemistry.

SUBSTANCE: method of making photoelectric converter based on GaAs involves growing by liquid-phase epitaxy on n-GaAs substrate a base layer of n-GaAs doped with tin or tellurium, with thickness of 10–20 mcm and a layer of p-AlxGa1-xAs, doped with zinc, for x = 0.2–0.3 at beginning of growth and x = 0.10–0.15 in surface region of layer, wherein layer of p-AlGaAs is grown carried at temperature 600–730 °C for 20–50 minutes, during this period method includes formation of diffusion p-n junction in GaAs with formation of an emitter layer of p-GaAs with thickness of 1–2 mcm, deposition of back contact by thermal vacuum sputtering, annealing deposited back contact in a hydrogen atmosphere, deposition through a photoresist mask of a front contact by thermal vacuum sputtering and annealing deposited front contact in a hydrogen atmosphere, metallization of front contact by galvanic deposition through a photoresist mask with simultaneous deposition of gold on rear surface, separating etching structure through photoresist mask into separate photocells and application of antireflection coating.

EFFECT: invention enables to make photo converters with increased efficiency of conversion of narrow-band, in particular, laser radiation, and can be used in mass production of GaAs photocells.

3 cl, 2 dwg, 2 ex

 



 

Same patents:

FIELD: chemistry.

SUBSTANCE: method of obtaining sensitive element of thermal receiver matrix based on vanadium oxide represents application of vanadium metal film and electrodes by methods of magnetron dispersion and further lift-off lithography on dielectric substrate. After that, high-density electric current is passed through vanadium metal film, which results in its heating and thermal oxidation. After structure heating and formation of oxide VOx, current isswitched off, and cooling of formedthin-filmed element takes place.

EFFECT: invention makes it possible to considerably simplify method of manufacturing sensitive element of thermal receiver matrix.

2 cl, 1 dwg

FIELD: chemistry.

SUBSTANCE: PbSnSe substitution solid solution films are highly requested by solid-state electronics and middle and far infrared lasers. However, the current tin content in hydrochemically synthesised PbSnSe films cannot provide their far infrared light-sensitivity completely. According to the making PbSnSe substitution solid solution films by ion exchange process, -prepared PbSe films are processed in an aqueous solution of tin (II) salt solution containing soluble acetate or acetic acid in an amount of 6.0 mole/l or less at a process temperature of 353-371 K that is followed by the air treatment at a temperature from 523 to 723 K.

EFFECT: technical effect of the invention consists in a shift of the spectral light-sensitivity range of PbSnSe solid solution films prepared on an aqueous solution by ion-exchange process in the far infrared range.

1 tbl

FIELD: physics.

SUBSTANCE: method of producing pin-photodiodes with a guard ring on high-resistivity p-silicon includes thermal oxidation of the initial p-silicon wafer or an epitaxial structure comprising a layer of high-resistivity p-silicon, opening "windows" in the thermal oxide layer, depositing phosphorus atoms into the "windows" and distillation thereof combined with oxidation to form planar n+-p junctions of the operating region and the guard ring region, forming on the reverse side of the wafer a gettering layer and performing gettering, etching the gettering layer and doping the contact region of the base with boron atoms to form a p+-p type ohmic contact, opening in the oxide layer contact "windows" to the operating region and the guard ring and probing dark currents thereof, selecting wafers which do not correspond to given dark current values, etching out the thermal oxide layer therefrom and depositing on the free silicon surface a new protective layer silicon oxide at temperature not higher than 300°C, opening contact "windows" in the deposited layer and re-probing dark currents and if the dark current corresponds to given values, depositing a metal coating, forming a contact pattern and burning in the metal, and if the dark current does not correspond to the given values, repeating the operations until the given dark current values are achieved.

EFFECT: high output of non-defective photodiodes by reducing the level of dark current of the operating region and the guard ring region to given values.

2 cl, 1 tbl

FIELD: physics.

SUBSTANCE: fabrication of GaAs-based photo inverter comprises growth by liquid-phase epitaxy on n-GaAs substrate of buffer n-GaAs ply, base n-GaAs ply, emitter p-GaAs ply and p-AlGaAs ply with Al content in solid phase of 30-40 at % at the growth start and Al content in solid phase of 10-15 at % in the ply surface area. Rear contact and face contact are deposited. Anti-reflection coating is applied on substrate face surface.

EFFECT: safe process, lower costs, higher efficiency of conversion of laser radiation.

9 cl

FIELD: process engineering.

SUBSTANCE: invention relates to solid-state electronics, particularly, to fabrication of photo conducting radiation-resistant structures. This process comprises pre-formation of monoply of fat acid on the surface of lead-bearing salt solution in water in concentration of 1·10-3-5·10-3 mol/l to get said monoply by Langmuir- Blodgett process. Said one lead-bearing fat acid monoply is applied on photosensitive film surface. Said film is subjected to thermal sensitization. Note here that monoply transfer on photosensitive ply is performed by Langmuir- Blodgett process after said thermal sensitization. Pre-formation of monoply of fat acid is executed on the surface of lead-bearing salt solution in water at solution pH of 8.0±0.4.

EFFECT: higher radiation-resistance at high photo sensitivity and wide spectral range of photo sensitivity.

3 cl, 5 dwg, 6 tbl, 3 ex

FIELD: physics.

SUBSTANCE: offered invention relates to technology of manufacture of semiconductor devices, in particular, to methods of manufacture of planar large area pin-photo diodes based on high-resistance silicon of p-type conductivity. The method includes preparation of a plate of source p-silicon or silicon epitaxial structure of p+-p-type, formation of a mask for implantation of P+ ions into a working area and a security ring, two-phase implantation of P+ ions with the energy and the dose respectively (30÷40) keV and (3÷4)·1015 cm-2 on the first and (70÷100) keV and (8÷10)·1015 cm-2 at the second stage for formation of n+-p transitions of working area and the security ring, implantation of BF+2 ions with the energy (60÷100) keV and the dose (2÷3)·10 cm-2 from the back side of the plate, two-phase post-implantation annealing at duration and temperature respectively no less than 1 hour and (570÷600)°C on the first stage and no less than 5 hours and (890÷900)°C at the second stage, protection and an enlightenment of a surface of working area and protection of the periphery of the security ring by application of SiO2 film, and annealing, initial decrease of temperature after annealing up to 300°C and application of SiO2 film at the temperatures over 300°C is made in the conditions of oxygen lack, and implantation P+ and BF+2 ions is performed one after another in any sequence.

EFFECT: optimum selected implantation doses, modes and conditions of post-implantation annealing and conditions of application of protective and lightening coating provide increase of current sensitivity of pin-photo diodes at high background flares with preservation of low level of dark currents at decrease of complexity, labour input and energy consumption of manufacture.

2 cl, 1 tbl

FIELD: physics.

SUBSTANCE: invention relates to production of silicon p-i-n photodiodes which are sensitive to radiation with wavelength of 0.9-1.06 mcm. Said silicon p-i-n photodiodes are intended for use in different optoelectronic devices which require detection of short laser pulses (10-40 ns). After performing high-temperature thermodiffusion processes to form the photodiode structure: - thermal oxidation; - phosphorus diffusion to form n+-type regions (photosensitive areas and collar rings); - phosphorus diffusion into the back surface of the wafer to generate impurities; - boron diffusion into the back surface of the water after etching a gettering n+-type layer to form a p+-type layer, after forming ohmic contacts, the method includes etching the dielectric film from the silicon surface and etching silicon by a depth less than 1 mcm, followed by depositing a silicon dioxide film using a low-temperature technique at temperature not higher than 800°C. Ohmic contacts are then formed using known techniques.

EFFECT: reduced dark current of photosensitive areas and the collar ring, reduced values of coupling factors between the photosensitive areas of multielement photodiodes and high output of non-defective devices.

FIELD: physics.

SUBSTANCE: method for hybridisation of reading LSI chips and a photosensitive element array of photodetector devices includes pressing in indium microcontacts located on chips to be interfaced. The microcontacts are in the form of stretched rectangles with side dimensions smaller than the gaps between the microcontacts, both on the vertical and the horizontal. The microcontacts on the LSI chips and the photosensitive element array are located at an angle to each other.

EFFECT: high reliability of interfacing reading LSI chips and a photosensitive element array while preventing shorting of adjacent microcontacts.

5 dwg

FIELD: chemistry.

SUBSTANCE: invention relates to technology of manufacturing silicon p-i-n photodiodes (FD), sensitive to radiation with wavelengths 0.9-1.06 mcm. According to invention in method of manufacturing silicon p-i-n photodiodes, in order to reduce concentration of electrically active centres, created by contaminating admixtures with low values of diffusion coefficients, process of thermal oxidation is carried out at temperature not higher than 950°C and the following processes of diffusion (phosphorus diffusion to create n+-regions, gettering with diffusion n+- layer, boron diffusion to create p+-region) are performed at temperatures, which do not exceed the given one. In this case due to sharp reduction of diffusion coefficient of admixtures with reduction of temperature of processes (exponential dependence on temperature) mainly admixtures with high diffusion coefficients, which later are efficiently removed by means of gettering processes, penetrate into silicon volume.

EFFECT: reduced concentration of generation-recombination centres in i-region of photodiode, which results in reduction of FD dark current and increased percent of output of usable devices.

FIELD: physics.

SUBSTANCE: invention relates to photodiode technologies based on epitaxial GaN/AlGaN p-i-n structures which convert ultraviolet radiation. The invention discloses a method of producing a multi-element photodetector based on epitaxial GaN/AlxGa1-xN p-i-n structures. Production is carried out using a mesa technique of ion etching to a n+-AlGaN layer, heat-treating the surface of the mesa p-i-n diodes at 450-550°C for 90-200 s to heal radiation and stoichiometric defects formed on the perimeter the p-i-n diodes under the action of an ion beam or other surface damages arising on technological operations of producing a mesa structure.

EFFECT: reducing dark current of a multi-element photodetector.

2 dwg

FIELD: metal science; protection of materials against external and corrosive attacks.

SUBSTANCE: proposed method for producing diamond-like films designed for encapsulating solar photocells to protect them against chemical, radiation, and mechanical damage includes variation of ion kinetic energy, plasma discharge current, and spatial density distribution of plasma incorporating C+, H+, N+, and Ar+ ions by acting upon ion current from radial source with electric field built up by stop-down, neutralizing, and accelerating electrodes. Spatial plasma distribution is checked for uniformity by measuring plasma current density on solar photocell surface whose temperature is maintained not to exceed 80 oC. In the process substrate holder makes complex axial movement in three directions within vacuum chamber. Diamond-like films produced in the process on solar photocell surface area over 110 cm2 are noted for uniformity, difference in their optical parameters variable within desired range is not over 5%.

EFFECT: enhanced adhesive property, microhardness, and resistance of films to corrosive attacks.

5 cl, 12 dwg, 2 tbl

FIELD: electrical equipment.

SUBSTANCE: face side of semiconductor wafer whose structure has n-Ge substrate, n-GsAs buffer layer, n-GsAs base layer, p-GsAs emitter layer, p+-GsAlAs large-gap layer, and p+-GsAs contact layer is covered with silicon dioxide layer. Contact metallization layer is evaporated on rear side of wafer. Protective photoresist layer is formed on silicon dioxide layer and rear contact is built up by electrochemical deposition. Photoresist mask with windows is made upon removal of photoresist above contact regions of photoelectric converter. Then silicon dioxide layer is etched in windows and chromium metal contact layers are alternately evaporated. Upon producing photoresist mask with contact pattern contacts are built up by electrochemical deposition of silver and protective layer of nickel. Upon removal of photoresist evaporated layers of contact metallization are removed by ion-beam etching, wafers are given heat treatment, and photoresist mask with window pattern over photoelectric converter perimeter is formed. Then silicon dioxide layer is removed from windows and gallium arsenide layers are etched to expose germanium substrate. Silicon dioxide layer is removed upon removal of photoresist and antireflecting coating is applied upon etching p+-GsAs beyond contact regions.

EFFECT: improved quality of face contacts due to adhesion, reduced contact resistance and noble metal consumption.

1 cl, 8 dwg

FIELD: electronic engineering; fabrication of semiconductor photoelectric generators.

SUBSTANCE: proposed method for fabricating photoelectric generator includes formation of p-n structures on semiconductor substrate, metal deposition, cutting of blank into matrices, their covering with clearing coat, and connection of current leads; multilayer n-p structure is formed by way of epitaxial growth of n and p layers on semiconductor substrate; prior to connection of current leads pulse voltage is applied to matrices and reverse-biased p-n junctions are broken down.

EFFECT: enhanced output voltage and power, well productivity, and manufacturability of generator.

1 cl, 6 dwg

FIELD: semiconductor microphotoelectronics.

SUBSTANCE: proposed method for manufacturing photodetector depending for its operation on accumulation of charge in potential wells includes production of diamond substrate in the form of wafer and deposition of metal contacts thereon. Diamond wafers chosen for substrate has nitrogen concentration not over 2 · 1019 cm-3. Some of these contacts are placed at substrate potential and are common for external circuit, and potential wells are made under other contacts for accumulating supports of charge divided at metal-to-semiconductor barrier by maintaining "floating" potential across these contacts relative to substrate. Proposed photodetector is characterized in reduced probability of detecting signal from false source ranging between hundreds of nm and 50 nm with sensitivity threshold brought to physical one at λmax = 220 nm.

EFFECT: reduced band of ultraviolet radiation detected by device.

1 cl, 2 dwg

FIELD: optical electronics, in particular, engineering of devices, transforming beam energy to electrical energy, possible use for measuring light level, intensiveness of radiation, dose of ultraviolet radiation in agro-industrial complex and as sensor for determining concentration of ozone in atmospheric layer of Earth.

SUBSTANCE: method includes applying photo-sensitive layer of organic semiconductor onto substrate of non-organic semiconductor and positioning of these between electrodes, one of which is semi-transparent. As non-organic semiconductor, n-type gallium arsenide is utilized (n-GaAs), and as organic semiconductor, thin layer of copper phthalocyanine of p-type is applied, between layer of n-type and layer of p-type, layer of native semiconductor is positioned (i-layer).

EFFECT: increased photo-sensitivity in photo-EMF in wave length range 400÷500 nanometers.

1 dwg

FIELD: manufacturing optical devices including semiconductor optoelectronic ones.

SUBSTANCE: proposed method used for manufacturing optical and semiconductor optoelectronic devices, such as laser diodes, optical modulators, optical amplifiers, optical switching units, and optical detectors, involves device manufacture from part of chip of quantum potential well structure including stage of device chip treatment by plasma etching so as to produce elongated defects at least in part of layer covering part of device chip as stage in technology of mixing quantum potential wells for next stage of thermal annealing.

EFFECT: improved process of mixing quantum potential wells.

22 cl, 9 dwg

FIELD: photoelectric modules for electrical energy generation.

SUBSTANCE: proposed photoelectric module built around single-crystalline silicon covered with polymeric film applied thereto by potential-static cycling method and characterized in conversion efficiency of 70-90% and wavelength band of 3·10-2 to 10-11 cm has its photoconverter made of single-crystalline silicon base material coated with polymeric film applied thereto by potential-static cycling method; this film is made of mixture of conducting polymers (polystannum aniline, polysilane aniline, and polyaniline), their proportion being as follows: 10 : 8 : 4. Invention specification also gives method for manufacturing this silicon-polymer module.

EFFECT: enhanced conversion efficiency and enlarged wavelength band.

2 cl, 1 ex

FIELD: technology for making devices, transforming light to electric energy.

SUBSTANCE: method for making photo-transformer on semiconductor plate with structure n-Ge substrate, n-GaAs buffer layer, n-GaAs base layer, p-GaAs emitter layer, p+-GaAlAs wide-zone layer, p+-GaAs contact layer, includes spraying contact metallization layer onto back of plate, forming protective photo-resist layer, growing of back contact by electro-chemical sedimentation of silver, removal of photo-resist, serial spraying of contact metallization layers of chromium 200÷400Å thick, of palladium 200÷500Å thick, of silver 500÷1500Å thick, creation of photo-resistive mask with pattern of contacts, growing of contact by electro-chemical sedimentation of silver, removal of photo-resist, etching together of sprayed layers of contact metallization by means of ion-beam etching, thermal processing of plate, creation of photo-resistive mask with pattern of windows along perimeter of photo-transformer, etching of gallium arsenide layers up to germanium layer, removal of photo-resist, etching together of layers of p+-GaAs layer beyond limits of contact areas and application of anti-reflecting cover. After spraying of contact metallization layer onto back, thermal processing of plate is performed and sprayed serially are contact metallization layers of chromium at temperature of 300÷350Å, palladium and silver at temperature of 200÷250Å. After removal of photo-resistive mask with contact pattern, layers of silver and palladium are etched together by means of ion-beam etching up to layer of chromium, further layer of chromium is removed in water solution of hydrochloric acid, and after etching of gallium arsenide layers up to germanium substrate and removal of photo-resist, p+-GaAs layer is etched together beyond limits of contact areas in water solution of lemon acid, lemon-acidic potassium and hydrogen peroxide at temperature of 40÷50°C.

EFFECT: improved quality of face contacts of transformer due to increased adhesion and decreased transfer resistance.

4 dwg

FIELD: photodetector and photodetector device manufacturing technique.

SUBSTANCE: proposed method for assembling radio components of infrared radiation photodetectors built around lead chalcogenide photoresistors and designed to operate in spectral region of 1 to 5 μm involves use of quick-sealing polymeric adhesive polyorganosiloxane urethanes under fast curing conditions for assembling infrared-radiation photodetectors from different components based on lead chalcogenide photoresistors by gluing them together due to introduction of polymerization reaction catalyst (tin diethyl caprylate) in silicone triol and organic diisocyanate (toluylene diisocyanate) compound.

EFFECT: improved manufacturing technique due to reduced adhesion time.

1 cl, 1 tbl

FIELD: measurement technology; aerospace engineering; flying vehicle manufacture.

SUBSTANCE: coherent flat-wavefront beam is passed through photoelectric displacement-to-code transducer made in the form of p-n junction along single optical axis and directed to transducer plane. Diffraction microrelief is formed on photocell surface, its parameters and those of light beam being tightly interrelated by equation f = 2λ/b, where f is angle of light beam divergence in direction of point of observation; λ is light beam wavelength; b is diffraction microrelief slot width.

EFFECT: enhanced sensitivity, speed, efficiency of light beam absorption by photocell, eliminated blurring effect on photocell surface.

2 cl, 1 dwg

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