The method of obtaining quantum-size semiconductor structures
(57) Abstract:Use: in the manufacture of quantum-size semiconductor structures. The inventive method includes the formation of quantum-dimensional regions in the process of growing structures by molecular-beam epitaxy. The formation produced by the monochromatization and focusing of the beam of dopant atoms with the subsequent direction of the atom beam on the diffraction element, the selection of the diffracted beam of the first diffraction maximum and its direction on the surface epitaxially patterns. 7 C. p. F.-ly, 1 Il. The invention relates to microelectronics, in particular to a technology for thin-film epitaxial structures for quantum-well semiconductor devices.One of the main trends in the development of semiconductor electronics at the present time is to increase speed and reduce power consumption of semiconductor devices (in particular, transistors) with a further increase in the degree of miniaturization.Effective means of solving these problems is the creation of quantum devices in which the linear dimensions of the IDT-regular electronic States, in which the electron motion is restricted or in two directions ("quantum threads"), or in all three dimensions ("quantum dot") 
When electrons are confined in a limited potential barriers in the field of space, comparable in size with the wavelength of the electron, begin to show their wave properties and they can tunnel through restrictive barriers. In addition, there appear two interrelated size quantization effect and resonance. Realization of devices running on these effects, allows to provide the switching speed close to the maximum achievable by tunneling, and low power consumption (due to the small size of the quantum device) because of quantum effects, the current is very sensitive to changes in applied voltage.This leads to the importance of obtaining quantum-well structures (in particular, epitaxial), in which the conduction electrons are concentrated in the areas of structure, located in the upper layer, and the linear dimensions of which are comparable to the electron wavelength (e.g. 200 for GaAs at T 20aboutC).A method of obtaining one dimensional conductive about the persons is the following. In politology GaAs substrate implanted Si ions, forming it conductive layer with a width of 20 μm. Then by means of rapid thermal annealing is performed to activate the implanted state, after which the substrate is implanted ions Si2+forming in her high-resistance region with a width of 0.1 μm, limiting conductive layer in a very narrow channel.Width channel with a one dimensional conductivity ("quantum threads") varied in the range of 0.2 to 1.0 μm. The conductivity of the channel decreased with decreasing width d and reached zero at d of 0.48 μm and very low temperatures (about 1.3 to 2.2).The disadvantage of this method is the occurrence of a matrix material radiation damage caused by the introduction of foreign ions (in this case, ions of Si in GaAs).Over time the distribution of defects in the matrix material is changed, which leads, ultimately, to the uncontrolled change of parameters of semiconductor.As a prototype of the proposed method the chosen method of obtaining quantum-well epitaxial structures ("quantum wires"), which consists in growing the epitaxial substrate structure, with the bulk doping an impurity of Verkhnee surface structure is formed system "quantum wires with cross-sectional dimension of 250-550 nm  it should be noted, that the width of electronic channels is smaller than the geometrical width and is about 100-150 nm, which is associated with the production technology.However, using the technique of photolithography, in particular etching agents for forming the desired pattern on the resist, leads to contamination of the semiconductor material extraneous inclusions and further reduces its parameters.This method does not allow one dimensional e-channels with preset width (due to the effects of protravlivanija) at the edges of the Windows in the resist width of electronic channels get less than their geometric width equal to the transverse size of the "window").In addition, the width of the generated electronic channels limited to the above effects, the size of slots in the resist. Using photolithography determines the complexity of this method.The task of the invention decrease the size and improve the accuracy of formation of quantum-well regions, increasing the purity of the structure and simplification of the way.The invention consists in that in the method of obtaining quantum-well epitaxial structures, namely in the direction of podlozku areas referred to region to form by monochromatization and focusing of the beam of dopant atoms with the subsequent direction of the beam of atoms on deficieny element, separation of the diffracted beam of the first diffraction maximum and its direction on the surface of the epitaxial structure, and a constant d of the diffraction element selected from a ratio
d , (1) where M is the mass of the atom dopant, kg;
is the diffraction angle, ug. the hail.T the temperature of the atoms of the beam of dopant, TO;
h the Planck constant, JS;
k Boltzmann's constant, j/K.Monochromatization atoms beam dopant is carried out by laser cooling.The beam of dopant atoms incident on the diffraction element, focuses in the form of a point or line (point or line focus) depending on the desired form of quanta of dimensional quantum dot or a quantum filament, respectively.As a component of the grown epitaxial structure can be used the elements of the III and V groups (e.g., As, and Ga), or the elements of group IV (Si, Ge), and as a dopant of Si and b respectively.The drawing shows the e in a vacuum chamber (not shown) of the substrate 1, on which is grown an epitaxial structure, molecular sources 2 component of the grown structures oriented on the substrate 1, the molecular source 3 of dopant atoms, lasers 4 located outside the vacuum chamber, with a system of mirrors 5, the focusing system made in the form of a set of collimating slits 6, the diffraction element 7, the mobile device 8 cooling and movable bounding the aperture 9.Collimating slits 6 are in the form of a diaphragm with a circular or rectangular holes (the size of a few tenths of a mm) and serve to cut out the beam of dopant atoms areas round or linear cross-section on the surface of the diffraction element 7 (point or line focus). The use of the slits 6 allows you to focus the beam of dopant atoms on different parts of the diffraction element 7 and get further set quatorzieme areas on the substrate 1.As the diffraction element 7 are used for amplitude or phase grating with a spectral range of 5-20 .The unit 8 cooling diffraction element 7 is made in the form of cryopanel, allowing Trogo element 7. Based on the ratio of the wolf-Braggot
2d sin = m, (2) where is the diffraction angle (the angle between the direction of the atomic beam and the plane of the diffraction element);
m the order of diffraction peak;
the wavelength de Broglie; expressions for
, (3) where M is the mass of the atom dopant;
V the velocity of the atom dopant;
h is Planck's constant; and the ratio between kinetic and thermal energy of the flow of atoms
kT, (4) where T is the temperature of the atoms in the stream;
k Boltzmann's constant; get
d (6) 7,010 M-27kg (weight of Si atoms), 10about, T 1, m 1, we have d 10 . This value d is T 15 K, = 3about. The values of T 4 and = 10aboutcorresponds to d 5 .The proposed method is implemented as follows.On the substrate 1 are directed molecular flows from sources 2, in which the substrate 1 is formed by epitaxial heterostructure (for example, AlGsAs/ /Gs As). Simultaneously with the formation of the upper layer of the structure is its alloying. Turns on the heater source 3 dopant atoms and, for example Si, proceed into the space between the source 3 and collimating slits 6. Laser 4 that is configured on castoroides using a system of mirrors 5 in beam, propagating towards the atomic beam. Due to the radiation pressure of the laser radiation is slowing and cooling of the atoms of the beam, which minimizes the dispersion of the atoms energy. SelectL<aboutcauses the atoms of the beam will be relative to the laser beam, the required speed and the Doppler shift to strongly absorb the laser light.The use of laser cooling allows to obtain a beam of atoms with a temperature of several millikelvin (MK). For the proposed method requires a temperature of a few Kelvin (4-10). Next monochromatically beam Si atoms are passed through the collimating slits 6, is supplied to the surface of the diffraction element 7 and is reflected from it in the form of diffraction dots or lines. Aperture 9 highlights of this combination line corresponding to the maximum of the first order, resulting in the surface of the substrate 1 is formed a quantum dot or quantum wire" (depending on the shape of the collimating slits 6) by a few .The size of the "quantum" field doping is defined as:
L where L is the distance from the diffraction element to the substrate 1;
T temperature is UP>-8and L 10 cm on a substrate can be obtained quantum-dimensional region with transverse size 10 . 1. The METHOD of OBTAINING QUANTUM-SIZE SEMICONDUCTOR STRUCTURES, which includes the cultivation of doped structures by molecular-beam epitaxy and the formation of quantum-dimensional regions, characterized in that the formation of quantum-well regions are produced in the process of growing structures through mohamedsalay and focusing of the beam of dopant atoms with the subsequent direction of the atom beam on the diffraction element, the selection of the diffracted beam of the first diffraction maximum and its direction on the surface of the epitaxial structure, and the constant d of the diffraction element selected from a ratio
< / BR>where M is the mass of the atom dopant, kg;
q is the diffraction angle, deg;
T is the temperature of the atoms of the beam of dopant, TO;
is the Planck constant, j;
k is the Boltzmann constant, j / K.2. The method according to p. 1, characterized in that monochromatization beam of dopant atoms is realized by means of laser cooling.3. The method according to p. 1, characterized in that exercise point picture display ambient is linear focusing of the primary beam of dopant.5. The method according to p. 1, characterized in that as component of the grown epitaxial structure using the elements of the III and V groups.6. The method according to PP.1 and 5, characterized in that as the dopant used silicon.7. The method according to p. 1, characterized in that as component of the grown epitaxial structure using the elements of group IV.8. The method according to PP.1 and 7, characterized in that as the dopant used Bor.
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: 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
FIELD: electronic engineering; materials for miscellaneous semiconductor devices using gallium arsenide epitaxial layers.
SUBSTANCE: intermetallic compounds chosen from group incorporating tin arsenide SnAs, palladium antimonide PdSb, manganese polyantimonide Mn2Sb, nickel stannate Ni3Sn2, nickel aluminate Ni2Al3, nickel germanate Ni2Ge, and cobalt germanate Co2Ge are used as materials of substrates for growing gallium arsenide epitaxial layers.
EFFECT: enhanced structural heterogeneity of gallium arsenide layers being grown.
SUBSTANCE: invention relates to vacuum technology and the technology of making carbon nanotubes, such as carbon nanotubes at ends of probes, which are used in probe microscopy for precision scanning. The method of making probes with carbon nanotubes is realised by depositing carbon films with nanotubes through magnetron sputtering in a vacuum at direct current of 100-140 mA using a carbon target with a nanotube growth catalyst. Work pieces of the probes are put into a vacuum installation. A carbon film with nanotubes is then sputtered in a residual atmosphere of inert gas.
EFFECT: invention allows for obtaining probes with carbon nanotubes, lying perpendicular the surface of the probe, in required amounts without using explosive substances and complex devices.
SUBSTANCE: invention can be used in manufacturing organic light-emitting diodes, liquid-crystal displays, plasma display panel, thin-film solar cell and other electronic and semi-conductor devices. Claimed is element, including target of ionic dispersion, where said target includes processed MoO2 plate of high purity. Method of such plate manufacturing includes isostatic pressing of component consisting of more than 99% of stoichiometric MoO2 powder into workpiece, sintering of said workpiece under conditions of supporting more than 99% of MoO2 stoichiometry and formation of plate which includes more than 99% of stoichiometric MoO2. In other version of said plate manufacturing component, consisting of powder, which contains more than 99% of stoichiometric MoO2, is processed under conditions of hot pressing with formation of plate. Method of thin film manufacturing includes stages of sputtering of plate, which contains more than 99% of stoichiometric MoO2, removal of MoO2 molecules from plate and application of MoO2 molecules on substrate. Also claimed is MoO2 powder and method of said plate sputtering with application of magnetron sputtering, pulse laser sputtering, ionic-beam sputtering, triode sputtering and their combination.
EFFECT: invention allows to increase work of output of electron of ionic sputtering target material in organic light-emitting diodes.
16 cl, 5 ex
SUBSTANCE: in method for growing of silicon-germanium heterostructures by method of molecular-beam epitaxy of specified structures due to silicon and germanium evaporation from separate crucible molecular sources on the basis of electronic-beam evaporators, silicon evaporation is done in automatic crucible mode from silicon melt in solid silicon shell, and germanium is evaporated from germanium melt in silicon insert, which represents a previously spent hollow residue, produced as a result of silicon evaporation in automatic crucible mode, and arranged in crucible cavity of cooled case of crucible unit of electron-beam evaporator used to develop molecular flow of germanium. At the same time process of epitaxy is controlled with account of germanium deposition speed selection, determined from given dependence.
EFFECT: increased stability and expansion of assortment of generated high-quality silicon-germanium heterostructures as a result of improved control of molecular-beam epitaxy of heterostructures due to accurate control of silicon and germanium deposition mode in the optimal range of speed values, reduction of concentration of uncontrolled admixtures in heterostructures produced by proposed method, and reduction of resource expenditures for preparation of process equipment.
2 cl, 3 dwg
SUBSTANCE: invention relates to the field of nanotechnologies and may be used to form nanostructures from evaporated microdrop by exposure to acoustic fields. Complex for formation of nanostructures comprises a nanostructures shaper, an optical microscope, a data display facility and information processing and complex control facility. The nanostructures shaper comprises a foundation and a source of shaping action, at the same time the foundation is formed as piezoelectric with the possibility to apply initial substrate on its surface, and the source of nanostructure-shaping action is represented by surface acoustic waves (SAW), besides, to develop a SAW line, a pair of interdigital transducers (IT) is located on the piezoelectric foundation with the possibility to excite the acoustic field between them, and the shaper is installed in the object area of the optical microscope, at the same time the axis of the microscope sighting is aligned relative to the foundation at the angle φ, besides, the complex also includes a generator of high-frequency oscillations and a wideband amplifier connected to it and to IT.
EFFECT: provision of universality as regards a class of objects exposed to nanostructuring.
12 cl, 1 dwg, 1 tbl
SUBSTANCE: invention relates to the field of nanotechnologies and may be used to make ordered nanostructures, used in micro- and nanoelectronics, optics, nanophotonics, biology and medicine. The proposed method may be used to manufacture single-layer and multilayer nanostructures, also the ones containing layers of different composition, and also two-dimensional, three-dimensional ordered structures of various materials. According to the method, the substrate and the initial substrate, containing nanoparticles, are arranged to form a space between them. The substrate is sprayed in the specified space in the form of a cloud of drops, every of which contains at least one nanoparticles. Creation of a substrate in the form of a sprayed cloud of drops is done by means of ultrasound exposure, when the source of ultrasound effect is located relative to the substrate with the possibility to arrange a sprayed cloud of drops in the specified space. Control of motion in the specified space and drops deposition onto the substrate is carried out through their exposure to external electric and/or magnetic fields.
EFFECT: wider class of materials, which could be used to form ordered nanostructures, higher accuracy of nanoobjects reproduction, stability of nanostructures formation process in one technological space.
FIELD: power engineering.
SUBSTANCE: films and layers of tellurium with single-crystal structure are produced on crystal faces by means of tellurium conversion into a monatomic steam and growth of single-structure specimens from it, at the same time the process of deposition is carried out in atmosphere of hydrogen at PH2=1.8 atm, temperature of initial tellurium T2=600°C and temperature of substrate zone T1=400°C.
EFFECT: production of films and layers of tellurium of single-crystal structure at orienting substrates.
SUBSTANCE: vacuum sputtering plant comprises a resistive source of an evaporated material connected to a power supply unit, and facing with the first side towards the substrate, on which a semiconductor structure is generated, and with the second one - to a receiver of charged particles connected to a negative terminal of a source of accelerating voltage, to a positive terminal of which voltage is connected. The receiver of charged particles may be arranged in the form of a plate of a refractory metal.
EFFECT: higher stabilisation of an evaporation speed, reproducibility of sputtered material layers by thickness and higher quality of manufactured structures.
4 cl, 1 dwg