Semiconductor ferromagnetic hetero-structure
FIELD: non-organic chemistry, namely triple compound of manganese-alloyed arsenide of silicon and zinc arranged on monocrystalline silicon substrate, possibly in spintronics devices for injection of electrons with predetermined spin state.
SUBSTANCE: electronic spin is used in spintronics devices as active member for storing and transmitting information, for forming integrated and functional micro-circuits, designing new magneto-optical instruments. Ferromagnetic semiconductor hetero-structure containing zinc, silicon, arsenic and manganese and being triple compound of zinc and silicon arsenide alloyed with manganese in quantity 1 - 6 mass % is synthesized on substrate of monocrystalline silicon and has formula ZnSiAs2 : Mn/Si. Such hetero-structure is produced by deposition of film of manganese and diarsenide of zinc onto silicon substrate and further heat treatment of it.
EFFECT: possibility for producing perspective product for wide usage due to combining semiconductor and ferromagnetic properties of hetero-structure with Curie temperature significantly exceeding 20°C and due to its compatibility with silicon technique.
3 ex, 2 dwg
The invention relates to the field of inorganic chemistry, specifically to alloyed manganese ternary arsenides silicon and zinc, located on the monocrystalline silicon substrate, which can find application in spintronic devices for injection of electrons with a certain spin state. In spintronic devices electronic spin is used as the active element for the storage and transmission of information, the development of an integrated and functional circuits, design of new magnetoelectronic devices.
The above ternary arsenides silicon and zinc belong to the class of arsenides elements of the second and fourth group of the Periodic system.
Currently, the most promising materials for spintronics are connections based on semiconductors And3B5,doped Mn, Co, Fe [M.L.Reed, M.K.Ritums, H.H.Stadelmaier, M.J.Reed, C.A.Parker, S.M.Bedair, and N.A.El-Masry, Mater. Lett, 2001, 51, 500; M.L.Reed, N.A.El-Masry, H.Stadelmaier, M.E.Ritums, N.J.Reed, C.A.Parker, J.C.Roberts, and S.M.Bedair, Appl. Phis. Lett, 2001, 79, 3473; N.Theodoropoulou, A.F.Hebard, M.E.Overberg, C.R.Adernathy, S.J.Pearton, S.N.G.Chu, and R.G.Wilson, Phys. Rev. Lett., 2002, 89, 107203; Hideo Ohno. Properties of ferromagnetic III-Y semiconductors. Journal of magnetism and magnetic materials. 1999. V.209. P.110-129]. The best results in this group of compounds were obtained on samples of (Ga, Mn) N with temperature of the magnetic ordering (Curie temperature TC), equal K [G.T.Thaler, M.E.Overberg, BGila, R.Frazier, C.R.Abemathy, SJ.Pearton, J.S.Lee, S.Y.Lee, Y.D.Park, Z.G.Khim, J.Kim, and f.ren, appl. Phys. Lett, 2002, 80, 3964]. The disadvantages of these materials include structural imperfections, a large number of defects, is not sufficiently high Curie temperature and a significant difference in the crystal structures between semiconductors And3B5and silicon, making it difficult to obtain epitaxial structures and makes them incompatible with silicon technology. It should be noted that the vast majority of the elemental base of solid state electronics devices made on silicon-based.
Compounds that are compatible with silicon technology, are the mono-silicides of the transition metals Fe1-xMnxSi and Fe1-yCOySi, where x<0.8 a; y<0,3 [N.Manyala, Y.Sidis, J.F.DiTusa, G.Aeppli, D.P.Young, and Z.Y.Fisk, Nature Materials, 2004, 3, 255]. In these compounds, the highest Curie temperature Tc=K achieved in connection Fe1-yCOySi, which has an electronic conductivity, as for y<0.3 of a ferromagnet. The disadvantage of this material is low Curie temperature, which does not allow to create spintronic devices operating at room temperatures, i.e. at temperatures above 20°C.
Closest to the invention for magnetic and semiconductor properties is a ferromagnetic semiconductor Cd1-xMnxGeP2doped PE shodnymi d-elements, with high Curie temperature, belonging to the family of ternary semiconductors with the General formula And2B4With5 2[New magnetic semiconductor Cd1-xMnxGeP2. Gaedeke, Teshibari, Tnsi, Csato. FTP, 2001, t.35, B.3, p.á305-309]. The disadvantage of these compounds is poor compatibility with silicon technology.
The present invention aims at finding a ferromagnetic semiconductor product with a Curie temperature substantially above room temperature, which can be implemented in an industrial common silicon technology.
The technical result is achieved by the fact that a ferromagnetic semiconductor heterostructure, including zinc, silicon, arsenic and manganese, which is a triple compound of gallium zinc and silicon, doped with manganese in the amount of 1-6 wt.%, the specified connection is synthesized on a substrate of monocrystalline silicon and corresponds to the formula ZnSiAs2:Mn/Si, while the heterostructure is obtained by deposition of a film of manganese and diarsenide zinc on the silicon substrate with subsequent thermal processing.
The specified range of concentration of manganese is determined by the fact that when the content of Mn is less than 1 wt.% the resulting material does not possess ferromagnetic properties required for create the Institute of memory elements, and when the content of Mn is more than 6 wt.% the material is a multiphase and heterogeneous electrophysical properties.
The heterostructure ZnSiAs2:Mn/Si is produced by the interaction of the films of manganese and diarsenide zinc silicon substrate. The film is applied using vacuum thermal evaporation on oriented in the direction (111) single-crystal silicon substrate at a temperature of 30-100°With further heat treatment in the vapor diarsenide zinc at a temperature of 800-1000°C.
The parameters of the obtained material was monitored by scanning electron microscope (composition, film thickness), x-ray analysis (composition). Electrical conductivity of the samples was estimated by the method of van der Pauw, magnetic measurements in the temperature range from liquid helium to 600K was carried out using a SQUID-magnetometer.
Figure 1 shows the curve of the temperature dependence of the magnetization of ternary arsenide, silicon and zinc doped Mn. Figure 2 - characteristic conductivity ZnSiAs2:Mn depending on the temperature.
Below are examples of proposed compositions claimed heterostructures.
Example 1. Manganese sprayed on the silicon substrate to a film thickness 0,145 μm, and diarsenic zinc to the film thickness of 3.46 μm and annealed. The content of manganese arsenide, silicon and zinc status is made to 5.5 wt.%. The resulting sample has a Curie temperature TC=K (Figure 1, curve 1).
Example 2. Manganese sprayed on the silicon substrate to a film thickness 0,145 μm, and diarsenic zinc to the film thickness of 12.76 μm and annealed. The content of manganese arsenide, silicon and zinc is 1% wt.%. The resulting sample has a Curie temperature TC=K (Figure 1, curve 2).
Example 3. Manganese sprayed on the silicon substrate to a film thickness 0,125 μm, and diarsenic zinc to the film thickness of 1.85 μm and annealed. The content of manganese arsenide, silicon and zinc is 6.0 wt.%. The resulting sample has a Curie temperature TC=K (Figure 1, curve 3).
As can be seen from Figure 1, the claimed product is a ferromagnet with a Curie temperature substantially above room temperature TC=490÷K, and curve 2 indicates the semiconducting nature of the conductivity.
A unique combination of semiconducting and ferromagnetic properties declared heterostructures and compatibility with silicon technology make it a promising product for wide practical use.
Ferromagnetic semiconductor heterostructure, including zinc, silicon, arsenic and manganese, which is a triple compound of gallium zinc and silicon, doped with manganese in the amount of 1-6 wt.%, the specified connection is synthesized on the substrate m is nonrestoring silicon and corresponds to the formula ZnSiAs 2:Mn/Si, with heterostructure obtained by deposition of a film of manganese and diarsenide zinc on the silicon substrate with subsequent thermal processing.
FIELD: semiconductor technology; production of microelectronic devices on the basis of substrates manufactured out of III-V groups chemical element nitride boules.
SUBSTANCE: the invention is pertaining to production of microelectronic devices on the basis of substrates manufactured out of III-V groups chemical element nitride boules and may be used in semiconductor engineering. Substance of the invention: the boule of III-V groups chemical element nitride may be manufactured by growing of the material of III-V groups the chemical element nitride on the corresponding crystal seed out of the same material of nitride of the chemical element of III-V of group by epitaxy from the vapor phase at the speed of the growth exceeding 20 micrometers per hour. The boule has the quality suitable for manufacture of microelectronic devices, its diameter makes more than 1 centimeter, the length exceeds 1 millimeter, defects density on the boule upper surface is less than 107 defects·cm-2.
EFFECT: the invention ensures manufacture of the microelectronic devices of good quality and above indicated parameters.
102 cl, 9 dwg
FIELD: measuring equipment, possible use during manufacture of miniature semiconductor magnetic diodes for measuring devices, based on usage of galvanic and magnetic principles of information transformation.
SUBSTANCE: method for manufacturing magnetic diodes includes creating on face side of a high-ohmic semiconductor substrate of first conductance type of injector areas of magnetic diodes of second conductance type, creating contact areas of first conductance type with increased concentration of admixture and sensitivity adaptation of magnetic diode parameters, injection areas of second conductance type are formed as mesa structures, by diffusion of phosphor across whole surface of substrate and further local etch removal of alloyed layer outside injection areas, while sensitivity adaptation of magnetic diode parameters is performed by creation of crystals which contain more than one magnetic diode with different base length and selection of magnetic diode with required magnetic sensitivity value belonging to available range.
EFFECT: increased output of valid magnetic diodes, increased precision of sensitivity adjustment of magnetic diode parameters, expanded range of magnetic sensitivity in one batch, improved manufacturability of method, decreased loses during its realization with preserved parameters of magnetic diodes, manufactured by known methods.
FIELD: electronic engineering; manufacturing gallium arsenide based devices.
SUBSTANCE: proposed gallium arsenide based devices are manufactured from device structures with active-region electron concentration higher than required to ensure desired output parameters of devices; upon manufacture devices are irradiated with fast neutron fluency whose value is found from formula Fn=(1-K)/(7.2·10-4n0 -0.77) neutron/cm2, where Fn is neutron fluency value; K = n1/n0 is variation level of electron original concentration in device active region when irradiated with fast neutron fluency Fn; n0 is electron concentration in device active region before irradiation, cm-3; n1 is electron concentration in device active region after irradiation needed to provide for desired output parameters, cm-3; upon irradiation devices are given trial run with power continuously supplied to them at temperature of 85 ± 5 °C for 10-24 h.
EFFECT: enhanced resistance to irradiation with electrons and gamma-quanta.
1 cl, 1 dwg
FIELD: electronic engineering; manufacture of gallium arsenide based devices.
SUBSTANCE: proposed gallium arsenide based semiconductor devices are manufactured from device structures in which active-region electron concentration is higher than required to provide for desired output parameters; upon manufacture devices are irradiated with fast neutron fluency whose value is found from formula , where Fn is neutron fluency value; K = n1/n0 is variation level of original electron concentration in device active region when irradiated with fast neutron fluency Fn; n0 is electron concentration in device active region before irradiation; n1 is electron concentration in device active region after irradiation required to provide for desired output parameters, cm-3; after irradiation devices are subjected to heat treatment at temperature of 200 ±20 °C for 30 -60 min.
EFFECT: enhanced resistance of devices to irradiation with electrons and gamma-quanta.
1 cl, 1 dwg
FIELD: thin-film technology; hybrid integrated-circuit manufacture.
SUBSTANCE: proposed method for manufacturing microwave hybrid integrated circuit characterized in high-quality insulation of its circuit components, reduced probability of failure due to probable shorts at intersection points of image components and pendant wiring conductors and premature degradation of physical and chemical properties of current-carrying tracks, enhanced intervals between layout components at reduced gaps between its components includes creation of image of passive and switching components on substrate surface which are then covered with polyamide insulating layer by way of centrifuging interrupted to provide for certain time interval prior to reducing fluidity of polyamide varnish as it starts drying; during this time interval integrated circuit is held under condition of mentioned varnish spreading throughout entire surface of layout image of mentioned components including their side surface; clearances between component are filled up, and polyamide varnish is dried out. Then, while preparing integrated circuit to wiring of pendant components and conductors, double-layer shielding and insulating coating is formed on image surface at points of intersection of these components in the form of specially saved insulating layer combining functions of additional insulating layer preventing premature degradation of physical and chemical properties of image components and enhancing their insulation and contrast layer designed to improve optical-vision quality control by way of mentioned polyamide varnish photolithography using positive photoresist, as well as auxiliary positive photoresist layer on polyamide varnish insulating layer applied to surface of image components; both layers of this insulating coating are jointly subjected to thermal strengthening; mentioned layers are applied while forming double-layer shielding and insulating coating at the same time saving total thickness complying with main electrophysical parameters of integrated circuit affording admissible microwave mode of its operation.
EFFECT: facilitated manufacture, enlarged functional capabilities.
2 cl, 1 dwg
SUBSTANCE: proposed method used in manufacturing thick-film high-temperature superconductor circuit includes low-temperature firing of substrate followed by laser milling of grooves for paste and scanning with laser beam of area , where Sm is laser beam area in groove milling; Tev and Tmlt are material evaporation and substrate melting temperatures, respectively. Proposed method is characterized in maximal firing temperature reduced from 1600-1700 to 100-1100°C and, consequently, in reduced time, as well as in using laser packing of surface instead of high-temperature firing stage.
EFFECT: enhanced productivity, reduced power requirement.
1 cl, 2 dwg
FIELD: technology for making images of extremely high resolution.
SUBSTANCE: device has source for producing electromagnetic radiation in range of wave length 100 nm and below, space modulator, having multiple pixels, electronic system for processing and transferring data, receiving digital description of drawing, subject to being drawn, separating from it a series of partial drawings, forming said partial drawings as modulator signals and sending said signals into modulator, and precision mechanical system for moving said block and/or projection circuit relatively one another. Device also has electronic control system coordinating movement of block, sending signals into modulator and intensiveness of radiation, so that said drawing was sewn together of partial images, formed by series of partial drawings.
EFFECT: device using electromagnetic radiation source in waves range 100 nm and below.
8 cl, 7 dwg