RU2513655C1 - Magnetic field sensor and method of its manufacturing - Google Patents

Abstract

FIELD: measurement equipment.

SUBSTANCE: invention may be used to create miniature sensors for triaxial magnetometry. The magnetic field sensor comprises sensor units implemented using the Hall effect, which are made within a curvilinear shell with a system of layers. The system of layers includes functional and shaping layers that perceive the magnetic field. The latter provide for curvature of the shell and the possibility of orientation of cross-shaped Hall elements of sensor units in the space with arrangement of compliance between measured Hall voltages and orthogonal components of the external magnetic field vector. The method to manufacture a magnetic field sensor consists in the following. A multilayer film element/elements are formed on the substrate. At the same time they use materials, geometry and internal mechanical stresses providing for orientation of cross-shaped Hall elements of sensor units in the space, when there is compliance between the measured Hall voltages and orthogonal components of the external magnetic field vector. At the stage of formation of the film element they manufacture layers, shaping, mechanically stressed and functional, which perceive the magnetic field, with Hall contacts. The film element is separated from the substrate, transforming it under action of internal mechanical stresses into a shell with achievement of orientation of cross-shaped Hall elements in the space, when there is compliance between measured Hall voltages and orthogonal components of the external magnetic field vector.

EFFECT: solutions provide for achievement of accuracy and reliability of simultaneous measurements of orthogonal components of magnetic field, and also a component of magnetic field vector that is different from the one perpendicular to the sensor plane; increased reliability of a sensor and reproducibility of sensor parameters.

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Description

The invention relates to semiconductor devices - devices for measuring the magnetic field and their manufacturing technology, in particular to a Hall sensor and a method for its manufacture, and can be used to create miniature solid-state Hall sensors for triaxial magnetometry, intended for use in non-contact position sensors, angle sensors and linear movements (in the automotive industry and other areas of mechanical engineering), in orientation systems (electronic compasses), in active protection systems about magnetic fields, in medicine and biological research (invasive and non-invasive tracking of magnetic markers, for example, magnetic nanoparticles in the circulatory system of living organisms), in the study of magnetic materials (Hall microscopy probes), in determining the uniformity of the magnetic field and its gradient in research and commercial installations (sensitive metal detectors in weapon detection systems, tomographs, magnetic traps, laboratory magnets).

Known magnetic field sensor (L. Sileo, M.T. Tododaro, V. Tasco, M. DeVittorio, A. Passaseo "Fully integrated three-axis Hall magnetic sensor based on micromachined structures", Microelectronic Engineering, 87 (2010), pp 1217-1219) containing a substrate, a first sensor assembly made on a substrate, a second and third sensor assemblies located outside the substrate, made up, respectively, of a first cantilever structure located outside the substrate at an angle of about 90 ° to it, the second cantilever structure located outside the substrate at an angle to it of about 90 °, the first and second cantilever the structures are connected to the substrate, respectively, by means of the first and second loop-like structures, bending beyond the substrate and bearing the corresponding cantilever structures, providing them with a predetermined spatial location. The sensor is implemented using the Hall effect.

As the substrate, a GaAs (100) substrate was used.

In the sensor, the first and second loop-shaped structures are made of layers of semiconductor materials containing internal mechanical stresses characterized by different lattice constants, the bending of each of the loop-shaped structures is ensured by the presence of mechanical stress resulting from the difference in the lattice constants.

In the sensor, each of the loop-shaped structures is made up of a first layer of one semiconductor material - In _0.2 Ga _0.8 As 10 nm thick, characterized by the first lattice constant, and a second layer of another semiconductor material - GaAs 260 nm thick, characterized by the second constant lattice, the first layer is located on the AlAs sacrificial layer made of a thickness of 75 nm on a GaAs substrate, the second layer is located on the first layer.

In the sensor, the first and second cantilever structures are made on the basis of a heterostructure with the aforementioned first and second layers of loop-like structures present in the cantilever structures and providing communication with the substrate, the heterostructure contains a sequence of layers: a 75 nm thick sacrificial AlAs layer made on a GaAs substrate, then located layers loop structures - mechanically strained layer In _0,2 Ga _0,8 As of thickness 10 nm and a GaAs layer of 260 nm thickness disposed further layers, structural layers are sensory about node - GaAs buffer layer 800 nm thick, In _0,15 Ga _0,85 As layer corresponding to a quantum well having a thickness of 10 nm, Al _0,25 Ga _0,75 As spacer thickness 5 nm, Si δ-doped layer the concentration of the dopant is 1.9 × 10 ¹² cm ⁻² , Al _0.3 Ga _0.7 As a barrier layer with a thickness of 45 nm and a GaAs “sar” layer with a thickness of 10 nm.

A mesostructure with a geometric configuration that defines the detecting area of the corresponding sensor node, a cross-shaped mesostructure (cross-shaped Hall element), from which ends (Hall contacts) current leads to ohmic contacts located on the substrate, is made in the sensor with respect to each sensor node along the heterostructure.

The magnetic field sensor was adopted as the closest analogue (publication No. 2261684 of the European application for the invention of the authors M.T. Todaro, L.Sileo, V.Tasco, M.DeVittorio, R. Kingolani, A. Passaseo, C. Giordano, application No. 10164576.0 from 06/01/2010, IPC: 8 G01R 33/02, published 08.02.2012, Bull. 2012/06) containing a substrate, the surface of which is defined as the base plane, the first sensor node located on the substrate on the first nodal surface in the first plane, which is strictly parallel to the specified reference plane, the first cantilever structure located outside the reference plane under scrap to the base plane (υ; α), which includes a second sensor node located on the second nodal surface that is parallel to the second plane, the second cantilever structure located outside the base plane at an angle to the base plane (υ; β), the composition of which is made the third sensor node located on the third nodal surface, which is parallel to the third plane, the first and second cantilever structures are structurally connected to the substrate, respectively, by means of the first and second loop basal structures bending beyond the base plane and bearing the corresponding cantilever structures, providing them with a predetermined location in space outside the base plane, the first and second loop-like structures are made thicker than the thickness of the first and second cantilever structures by manufacturing in the substrate the corresponding first and the second recess (windows) with a geometric configuration that defines the geometry of the loop-like structures, with mating (side) walls located at an angle (γ) to the bottom capacious.

In the sensor, the angles (υ; α), (υ; β) of the location of the cantilever structures with respect to the base plane are approximately equal to 90 °.

In the sensor, the angle (γ), under which the mating (side) walls of the recesses are located relative to the bottom, is from 10 ° to 70 °.

In the sensor, the first and second loop-like structures are made of layers of semiconductor materials containing internal mechanical stresses characterized by different lattice constants, the bending of each of the loop-shaped structures is ensured by the presence of mechanical stress resulting from the difference in the lattice constants.

In the sensor, each of the loop-shaped structures is made up of a first layer of one semiconductor material, characterized by a first constant lattice, and a second layer of another semiconductor material, characterized by a second constant lattice, the first layer is made sequentially, in the direction from the substrate, then the first layer, then a second layer, the first crystal lattice constant being greater than the second crystal lattice constant.

In the sensor, the first and second cantilever structures are made on the basis of a heterostructure, which includes, in addition to the first and second layers of loop structures, which are part of the heterostructure and provide communication with the substrate, layers located in the direction from the substrate after the layers of loop structures and related to the layers of the sensor assembly.

In the sensor, the first, second and third sensor nodes are implemented using the Hall effect based on, respectively, the first, second and third heterostructures, each of which is made flat, multilayer, including a sequence of layers of semiconductor materials located in the direction, respectively, from the first, second and the third plane, in which at least one of the layers is susceptible to a magnetic field.

In the sensor, a layer susceptible to a magnetic field is made containing a two-dimensional electron gas.

A mesostructure with a geometric configuration that determines the detecting area of the corresponding sensor node (cross-shaped Hall element) is made in the sensor for each planar heterostructure.

The disadvantages of the above analogues include the lack of accuracy and reliability of simultaneous measurements of the orthogonal components of the magnetic field, as well as the components of the magnetic field vector, which is different from the perpendicular to the plane of the sensor; low reliability of the sensor; low reproducibility of sensor parameters. The reasons that impede the achievement of a technical result are as follows.

The manufacture of the sensor is based on the so-called “microorigami” version of the microstructuring of semiconductor films under the influence of built-in mechanical stresses (P.O. Vacacco et al., Appl. Phys. Lett. 78, 2852 (2001)). The used version of the microstructuring of semiconductor films is rather complicated and not quite suitable, for example, for a precise task of positioning sensor nodes in space, which, in particular, is necessary for reliable and accurate two-, three-axis measurements. It is worth noting that the triaxial measurements of the magnetic field in the above works of L. Sileo and M. Todaro with employees were not demonstrated, apparently, due to the relative complexity and lack of reproducibility of the chosen variant of microstructuring. The technical solutions used use an “extensive” approach to their creation. The decisions are inherently irrationally excessive number of elements in the design. As a result, coordination of relationships and the mutual arrangement of elements in the structure for its proper functioning is complicated. Attention is drawn to the fact that the functional elaboration with respect to structural elements is insufficient, which to a certain extent leads to an irrationally excessive number of elements in the structure. Each of the elements performs only a highly specialized function for it. So, in the composition of solid-state curved shells used in the design — loop-shaped structures made on the basis of mechanically strained layers of semiconductor materials due to formed recesses (windows), the layers are used only to specify a curvilinear shape, which determines an exclusively passive function with respect to shells. The possibility of using layers in the curvilinear shell to perform sensor nodes is not considered. On the contrary, the active function in the sensor is performed by specially formed flat sections of the heterostructure, including those located directly on the substrate, and separated from the substrate with their location outside the substrate at the ends of loop-like structures, with coordination of the spatial arrangement relative to each other and the substrate. Moreover, to make the separated parts of the heterostructure flat in the composition of the latter, it is necessary to grow a rather thick buffer to compensate for the influence of the internal mechanical stresses of the layers of loop-like structures that are present in the heterostructure and tend to give curvature to the parts of the heterostructure separated from the substrate, which kept them flat before separation. With the approach used to construct the sensor, the heterostructures having a spatial orientation relative to each other at an angle of 90 °, on which the sensor nodes are made, according to the authors, should be strictly flat, which is not justified. In addition, we note the fragility of the structure. Instability and tendency to bend and stick to the substrate under the action of capillary forces in the case of extraction of the entire structure from liquid to air at the final stage of the sensor manufacturing (after releasing two loop-like structures and two sensor nodes from communication with the substrate by selective liquid etching) or in the case of liquid condensation on surface of the finished sensor.

A known method of manufacturing a magnetic field sensor (L. Sileo, M.T. Tododaro, V. Tasco, M. DeVittorio, A. Passaseo "Fully integrated three-axis Hall magnetic sensor based on micromachined structures". Microelectronic Engineering, 87 (2010) , pp1217-1219), which consists in the implementation of the following steps. A multilayer heterostructure is fabricated on a GaAs (100) substrate, containing successively a sacrificial layer, mechanically strained layers of a loop-like structure, and functional layers of the sensor assembly. Then, a mesostructure is performed with a geometric configuration defining a detecting area with respect to each sensor node — a cross-shaped mesa with an active area of 30 μm × 30 μm (cross-shaped Hall element) using photolithography and liquid etching. After that, recesses (windows) are formed with respect to the second and third sensor nodes for manufacturing loop-shaped structures and the location of these nodes outside the substrate on loop-like structures that are load-bearing, while the pattern of loop-like structures is set by means of photolithography and etching along the layers of the sensor node without affecting layers of loop-like structures. As a result, recesses (windows) are formed with smooth mating (side) walls located at an angle relative to the bottom of 15 °. Then, using photolithography, thermal spraying, the Lift-off technique, and subsequent rapid annealing in nitrogen at 430 ° C for 20 seconds, GeAu / Ni / Au ohmic contacts and current leads from the ends (Hall contacts) of the cross-shaped mesa (cross-shaped Hall element) are made positioning contact current leads along a recess in relation to the second and third sensor nodes. Finally, with respect to the second and third sensor nodes, they begin the stage of their location outside the substrate. The regions of the heterostructure that are to be freed from communication with the substrate, corresponding to loop-shaped structures and sensor nodes, are "outlined" by deep, with capture of the substrate, windows by means of photolithography and liquid etching, opening access for etching of the sacrificial layer. Then proceed to the implementation of selective etching of the sacrificial layer. By etching the sacrificial layer, these parts of the heterostructure are released from communication with the substrate and, under the action of internal mechanical stresses, they bend the layers of loop-like structures by placing flat sections of the heterostructure with sensor nodes located at the ends of the loop-shaped structures, freed from bond with the substrate, outside the plane of the substrate. The angle between the plane of the substrate in which the first sensor node is made and the planes of the second and third sensor nodes are set to 90 °. The angle is set by choosing the length of the loop-like structure and the radius of its curvature.

The closest analogue is the method of manufacturing a magnetic field sensor (M.T. Todaro, L. Sileo, G. Epifani, V. Tasco, R. Kingolani, M. DeVittorio, A. Passaseo “A fully integrated GaAs-based three-axis Hall magnetic sensor exploiting self-positioned strain released structures ", J. Micromech. Microeng., 20 (2010), 105013, pp1-6), which consists in the fact that a heterostructure is made on the substrate, which contains a sacrificial layer sequentially in the direction from the substrate, mechanically strained layers of a loop-like structure and functional layers of the sensor node, then perform a cross-shaped mesostructure that determines the detecting area of each sensor a knot (cross-shaped Hall element) by means of photolithography and liquid etching, and then recesses (windows) are formed in relation to the second and third sensor nodes for the manufacture of loop-like structures and the location of these nodes outside the substrate on loop-like structures that are carrier by means of photolithography and liquid etching, then make ohmic contacts and current leads from the ends (Hall contacts) of the cruciform mesostructure, disposing in relation to the second and third sensors recess nodes, recesses finally, with respect to the second and third sensor nodes, start operations of their location outside the substrate - the heterostructure sections with the made recesses and sensor nodes are limited to deep, with capture of the substrate, windows by means of photolithography and liquid etching, forming the first and second cantilever structures and opening access to the sacrificial layer for subsequent etching, selectively etching the sacrificial layer through the windows, release these parts of the heteros the structures from binding to the substrate and under the action of internal mechanical stresses give bending to the layers of loop-like structures by placing cantilever structures containing flat sections of the heterostructure with sensor nodes located at the ends of the loop-like structures freed from bond with the substrate, outside the plane of the substrate, in the direction normal to the substrate .

In the method, a GaAs (100) substrate is used as a substrate.

In the method, a heterostructure is made that contains a sacrificial layer, mechanically strained layers of a loop-like structure and layers of a sensor assembly sequentially in the direction from the substrate, in the following composition: a 75-nm-thick AlAs sacrificial layer made on a GaAs substrate, then layers of loop-shaped structures — a mechanical stress layer In _0.2 Ga _0.8 As 10 nm thick and a GaAs layer 260 nm thick, then layers that are the structural layers of the sensor assembly are located — a GaAs buffer layer 800 nm thick, In _0.15 Ga _0.85 As a layer corresponding to bulk well, 10 nm thick, Al _0.25 Ga _0.75 As spacer 5 nm thick, Si δ-doped layer with a dopant concentration of 1.9 × 10 ¹² cm ^-2 , Al _0.3 Ga _0.7 As barrier a layer 45 nm thick and a GaAs “sar” layer 10 nm thick. The layers are made by molecular beam epitaxy.

In the method, a cross-shaped mesostructure is carried out, which determines the detecting area of each sensor node (cross-shaped Hall element) by photolithography and liquid etching; in its manufacture, the GaAs “sar” layer is 10 nm thick, Al _0.3 Ga _0.7 As the barrier layer a thickness of 45 nm, and the latter is not completely etched, leaving about 5 nm. As a result, a cross-shaped mesostructure with an active area of 30 μm × 30 μm is formed.

In the method, recesses (windows) are formed with respect to the second and third sensor nodes for making loop-like structures and arranging said nodes outside the substrate on loop-shaped structures that are carrier, by means of photolithography and liquid etching, along the layers of the sensor node without affecting the layers of loop-like structures. The choice of the geometrical dimensions of the recess, with the rectangular shape of the length of its side along which the subsequent etching of the sacrificial layer will be carried out, in combination with the radius of curvature, depending on the value of the internal mechanical stresses of the layers of the loop-like structures and their thicknesses, determine the angle at which the cantilever structures are placed in space relative to the substrate. As a result, recesses (windows) are formed with smooth mating (side) walls located at an angle relative to the bottom of 15 °. The specified angle is performed to obtain good ohmic contact in the manufacture of ohmic contacts and current leads.

In the method, ohmic contacts and current leads from the ends of the cross-shaped mesostructure (Hall contacts) are made by arranging contact tracks along the recess for the second and third sensor nodes by means of photolithography, thermal spraying, the Lift-off technique, and subsequent rapid annealing in nitrogen at 430 ° C for 20 sec. In this case, GeAu / Ni / Au ohmic contacts and current leads are made. The GeAu layer is 30 nm thick, the Ni layer is 10 nm, the Au layer is 40 nm.

The disadvantages of the analogues of the manufacturing method include the lack of accuracy and reliability of simultaneous measurements of the orthogonal components of the magnetic field of the manufactured sensor, as well as the components of the magnetic field vector, which is different from the perpendicular to the plane of the sensor; low reliability of the sensor; low reproducibility of sensor parameters. The reasons that impede the achievement of a technical result are as follows.

The manufacture of the sensor is based on the so-called “microorigami” version of the microstructuring of semiconductor films under the influence of built-in mechanical stresses (P.O. Vacacco et al., Appl. Phys. Lett. 78, 2852 (2001)). Moreover, in the methods used microstructuring of semiconductor films is unnecessarily complex and not quite suitable, for example, for precision job positioning of sensor nodes in space, which, in particular, is necessary for reliable and accurate two-, three-axis measurements. It is worth noting that the triaxial measurements of the magnetic field in the above works of L. Sileo and M. Todaro with employees were not demonstrated, apparently, due to the relative complexity and lack of reproducibility of the chosen variant of microstructuring. Decisions inherent in excessively excessive number of operations for the manufacture of the entire structure. As a result, coordination of relationships and relative positions of elements in the manufacture of a structure for its proper functioning is complicated. The complexity of manufacturing, redundancy of operations - a consequence of insufficient functional development in relation to structural elements. Each of the manufactured elements performs only a highly specialized function for it. So, in the composition of solid-state curvilinear shells used in the design — loop-shaped structures made on the basis of mechanically strained layers of semiconductor materials, the layers are used only for specifying a curvilinear shape in order to locate sensor nodes of the sensor outside the substrate. To ensure this function requires the implementation of special operations for the manufacture of recesses (windows). The manufacture of flat sections of heterostructures with elements that perform an active function requires growing a sufficiently thick buffer in their composition to compensate for the influence of internal mechanical stresses of the layers of loop-like structures when separating them from the substrate, which tend to give curvature to the parts of the heterostructure that are made up of heterostructures. The heterostructures with spatial orientation relative to each other at an angle of 90 °, on which the sensor nodes are made, according to the authors, should be strictly flat, which is not justified. In the manufacture of the sensor, operations must be carried out taking into account the strict coordination of the spatial arrangement of heterostructures with sensor nodes relative to each other and the substrate.

The technical result of the group of inventions is:

- achieving accuracy and reliability of simultaneous measurements of the orthogonal components of the magnetic field, as well as the components of the magnetic field vector, different from perpendicular to the plane of the sensor;

- improving the reliability of the sensor;

- increase the reproducibility of the parameters of the sensors.

As a separate advantage of the proposed technical solutions, it should be noted the possibility of achieving measurements of the magnetic field gradient, including the time dependence of the magnetic field gradient.

Another advantage of the proposed solutions is to reduce the size of the sensor in the direction perpendicular to the substrate, and the ability to scale the sensor to the region of nanoscale, in at least one dimension (perpendicular to the substrate).

The technical result is achieved in a magnetic field sensor containing sensor nodes implemented using the Hall effect, while the sensor nodes are made up of a curvilinear shell with a system of layers, among which are susceptible to the magnetic field - functional and shape-forming, the latter is provided with a curvature of the shell and the possibility of orientation of the cross Hall elements of sensory nodes in space with matching the measured Hall stresses to the orthogonal components of the vector externally th magnetic field.

In the sensor, the sensor nodes are made for triaxial / biaxial measurements in two shells made of cylindrical shape and arranged relative to each other so that their generators are perpendicular to each other, each shell is equipped with sensor nodes with cross-shaped Hall elements, including pairs of Hall contacts oriented in space with compliance of the measured Hall stresses with the three orthogonal components of the external magnetic field vector due to the azimuthal angle between for pairs of Hall contacts of each of these shells, equal to 90 °, or sensor nodes are made for biaxial measurements in one shell made of a cylindrical shape with pairs of Hall contacts of cross-shaped Hall elements of sensor nodes oriented in space with the correspondence of the measured Hall stresses to two orthogonal components vector of the external magnetic field due to the azimuthal angle between the pairs of Hall contacts, equal to 90 °.

In the sensor, the sensor nodes are made for triaxial / biaxial measurements in two shells made of cylindrical shape and arranged relative to each other so that their generators are perpendicular to each other, each shell is equipped with sensor nodes with cross-shaped Hall elements, including pairs of Hall contacts oriented in space with compliance of the measured Hall stresses with the three orthogonal components of the external magnetic field vector due to the azimuthal angle between for pairs of Hall contacts of each of these shells, equal to 90 °, or sensor nodes are made for biaxial measurements in one shell made of a cylindrical shape with pairs of Hall contacts of cross-shaped Hall elements of sensor nodes oriented in space with the correspondence of the measured Hall stresses to two orthogonal components the external magnetic field vector due to the azimuthal angle between the pairs of Hall contacts, equal to 90 °, while from these sensor nodes in the composition of two shells for triaxial / biaxial measurements or sensor nodes as part of a single shell for biaxial measurements, an array is formed in which n≥2 sensor nodes are made exactly the same, with a given distribution in space.

In the sensor, the shell is located on the GaAs substrate and is connected with it due to the AlAs sacrificial layer made on the substrate.

In the sensor, the forming layers are made of pseudomorphic single crystal from materials characterized in the free state by different periods of the crystal lattice, for layers located on the outside of the shell, materials with a large period of the crystal lattice are used.

Forming layers in the sensor are made using GaAs and InGaAs materials.

In the sensor in the system of layers, among which are susceptible to the magnetic field - functional and forming, the forming layer is made susceptible to the magnetic field.

In a sensor in a system of layers susceptible to a magnetic field - functional and shape-forming, a layer susceptible to a magnetic field is made of GaAs or FePt.

In the sensor, the shell wall thickness is from about (5 ÷ 6) × 10 ^-10 to about 10 ^-5 m.

In the sensor, in a system of layers that are magnetic and susceptible to the magnetic field, functional and shape-forming, a quantum well is made in the form of a 13 nm thick GaAs layer with an electron gas with a concentration of the order of 10 ¹¹ cm ^-2 , the quantum well is located between Si-doped AlGaAs solid solution layers, layers in the sequence AlGaAs - barrier, GaAs - quantum well, AlGaAs - barrier are located in the shell between the layer of GaAs made on the side of the inner volume of the shell, which is a protective layer, and the forming layer located on the outside of the shell and made of InGaAs.

Two sensor assemblies are made in the sensor in the wall of the cylindrical shell, the mesostructures are lithographically formed on the inner side of the shell with the formation of cross-shaped Hall elements - Hall bridges, the channel for passing the current of the cross-shaped Hall element of the sensor node - the channel of the Hall bridge is located along the guide of the cylindrical shell, sensor pairs along the channel are two pairs of Hall contacts for measuring Hall voltage - potential contacts, in Doi pair of contacts are arranged on opposite sides of the channel, the azimuth angle between the pairs of contacts 90 °, common to the two sensor nodes connecting channel is common to the two current contacts of sensor nodes and a length πR / 2 or more, R - radius of curvature of the shell; in the case of a sensor operating on the basis of the ordinary Hall effect, the functional layer that is susceptible to the magnetic field, as well as the forming layer, is made of a cylindrical shape, in it the geometry of the cross-shaped Hall element - the Hall bridge is determined by the execution of current leads from current and potential contacts of the Hall bridges by lithography and subsequent deposition of Au are laid current leads to the contact pads located on the substrate, with ohmic contacts to the functional layer, ohmic contacts made by spraying a layer of germanium / nickel / gold, followed by annealing; in the case of a sensor operating on the basis of an extraordinary Hall effect, a functional layer that is susceptible to a magnetic field is made, in contrast to the forming layer, having a pattern in the form of two connected cross-shaped elements, which determines the geometry of the Hall bridge, the functional layer is obtained by preliminary applying a protective resist to the forming layer and forming in the resist a through window with a pattern in the form of two connected cross-shaped elements, followed by spraying FePt and phi into the window After deposition, removal of the protective resist, which has curvature, like the forming layer, in this case, the ohmic contacts to the functional layer are made directly at the protrusions of the Hall element - the Hall bridge, either on the contact pads, or between them at any point of the current leads, the latter are made also by lithography and subsequent deposition of Au and laid to the contact pads located on the substrate and also made of gold, in order to obtain an ohmic contact, the FePt and Au layers were carried out but lapped, moreover, if the ohmic contacts are made at the protrusions of the Hall bridge, then the place where the layers are overlapped is located at the protrusions, if the ohmic contacts are made at the contact pads, the current guide regions are covered with FePt, and the FePt and Au layers are made at the contact pads overlap.

The sensor is additionally equipped with signal processing circuits formed on the same substrate, on which the shell with sensor nodes is located.

The sensor nodes in the sensor are made as part of a curved shell, which is sealed in a solid matrix of non-magnetic material.

The technical result is achieved in a method of manufacturing a magnetic field sensor in which a multilayer film element / elements is formed on the substrate using materials, geometry and internal mechanical stresses that ensure the orientation of the cross-shaped Hall elements of the sensor nodes in space, in which the measured Hall stresses correspond to the orthogonal components of the vector external magnetic field, while at the stage of formation of the film element make layers, forms forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts, the film element is separated from the substrate, transforming it under the influence of internal mechanical stresses into the shell with the achievement of the orientation of the cross-shaped Hall elements in space, in which the measured Hall stresses correspond to the orthogonal components vector of an external magnetic field.

In the method, when forming a multilayer film element, all its structural layers are made in sequence from the substrate — forming, mechanically stressed, functional, susceptible to a magnetic field, with Hall contacts and current conductors, contact pad layers, while using planar technology, layer patterns are set, including including drawings defining the contours of the film element, drawings of forming, mechanically stressed, and functional layers susceptible to a magnetic field with Hall contacts, with current leads from the latter to the contact pads, contact pads.

In the method, before the formation of the multilayer film element, a sacrificial layer located on a substrate is grown, the film element is separated from the substrate by selective side etching of the sacrificial layer, and a GaAs substrate is used as the substrate.

In the method, the thickness of the multilayer film element is set from 5 × 10 ^-10 to 10 ^-5 m, while the layer patterns are formed lithographically, the subsequent separation of the film element from the substrate is carried out by removing the material of the element located under the film element, thereby providing directional bending of the film an element with the formation of a shell of a cylindrical shape with a radius R with sensor nodes with cross-shaped Hall elements - the Hall bridge, oriented in space with the implementation of the corresponding action of the measured Hall stresses to the orthogonal components of the external magnetic field vector, while the channel of the sensor node for passing the current of the Hall bridge is placed along the guiding cylindrical surface of the shell, pairs of Hall contacts for measuring Hall voltage are made in the sensor nodes — potential contacts, contacts are placed along the channel on opposite sides its azimuthal angle between the pairs of contacts of the Hall contacts is 90 °.

In the method, the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into a shell containing two sensor nodes, with the achievement of the orientation of the cross-shaped Hall elements of the sensor nodes in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector, by realizing directional etching, performing a given direction of bending of the released film element, and the direction of bending barium is set during the formation of a multilayer film element, when specifying layer patterns, including a pattern defining the contours of a film element, patterns of forming, mechanically stressed, and functional, susceptible to a magnetic field, layers with Hall contacts and conductors from the latter to contact pads, contact pads, moreover, the drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to contact pads, is formed with a common sensor nodes with a channel for transmitting current lying in the direction of bending of the film element with a channel length of at least πR / 2, R is the radius of curvature of the shell, and two pairs of Hall contacts for measuring Hall voltage are made in the sensor nodes — potential contacts, contacts are located along the channel on its opposite sides, the azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs πR / 2, R is the radius of curvature of the shell, each pair is designed to determine its orthogonal component of the external magnetic of the first field, the film element is transformed into a shell of a cylindrical shape, in the final case the shell is placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shell and cured, when two multilayer film elements are formed, their patterns are realized with the possibility of perpendicular bending directions and obtaining shells of cylindrical shape, the generators of which are perpendicular, the layer patterns of the first film element are repeated in the second film element with rotation ohm at 90 °, in the final shell is placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shells and cured.

In the method, form-forming, mechanically stressed layers are formed by epitaxy from crystalline materials with different lattice constants, observing the conditions of pseudomorphic growth, a functional, susceptible to magnetic field, layer is made by epitaxy from a semiconductor or sprayed from metal.

In the method, form-forming mechanically stressed layers are formed by epitaxy from crystalline materials with different lattice constants — GaAs and InGaAs, a functional, susceptible to magnetic field layer is made of GaAs or FePt.

In the method, a functional magnetic field susceptible layer is made in the form of a system of layers, among which there is a 13 nm thick GaAs quantum well with an electron gas with a concentration of about 10 ¹¹ cm ^-2 , a quantum well is placed between AlGaAs solid solution layers, for which δ-doping of Si was carried out, with the layers in the AlGaAs sequence, the layer corresponding to the barrier, the GaAs layer corresponding to the quantum well, the AlGaAs layer corresponding to the barrier, located between the GaAs layer, which is the protective layer, and the forming layer located on a substrate or sacrificial layer grown on a substrate and made of InGaAs.

In the method, the drawing of a functional layer that is susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads in the case of manufacturing a sensor operating on the basis of the ordinary Hall effect, is formed with an external circuit, the same as that of the forming layer, and the geometry of the cross of the Hall element - the Hall bridge is determined by the implementation of current leads, from current and potential contacts of the Hall bridges by lithography and subsequent application of Au, conductors are laid to the contact area dams located on a substrate with ohmic contacts to the functional layer, ohmic contacts are performed by sputtering a germanium / nickel / gold layer followed by annealing; in the case of manufacturing a sensor operating on the basis of an extraordinary Hall effect, a functional layer that is susceptible to a magnetic field is made with a pattern different from the forming layer having a pattern in the form of two connected cross-shaped elements, which determines the geometry of the Hall bridge, the functional layer is obtained by preliminary applying a protective resist on the forming layer and forming in the resist a through window with a pattern in the form of two connected cross-shaped elements with subsequent spraying we put in the FePt window and the final, after sputtering, removal of the protective resist, in this case, ohmic contacts to the functional layer are made directly at the protrusions of the Hall element - the Hall bridge, either on the contact pads, or between them - at any point of the current leads, the conductors are also made by lithography and subsequent deposition of Au and laid to the contact pads located on the substrate and made of gold, to obtain an ohmic contact, the FePt and Au layers are overlapped, and if the ohmic The contacts are made at the protrusions of the Hall bridge, the place where the layers are overlapped is located at the protrusions, if ohmic contacts are performed on the contact pads, the current guide regions are covered with FePt, and in the area of the contact pads, the FePt and Au layers are lapped, while lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation.

In the method, a multilayer film element / elements are formed on the substrate, respectively, for sensor nodes intended for biaxial measurements in one shell, or sensor nodes intended for three-axis / biaxial measurements in two shells, an array with n ≥2 precisely identical elements, taking into account their geometry and spatial orientation, with a given distribution in space, using materials, geometry and internal mechanical stresses providing orientation of the cross-shaped Hall elements of the array of sensor nodes for biaxial measurements or for three-axis / biaxial measurements in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector, while layers are formed at the stage of formation of each film element of the array mechanically strained, and functional, susceptible to magnetic field, with Hall contacts, each film element is ma the netting is separated from the substrate, transforming it under the influence of internal mechanical stresses into the shell with the achievement of the orientation of the cross-shaped Hall elements in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector, with the receipt of an array of sensor nodes for biaxial measurements in one shell, made exactly the same, with a given distribution in space, with n≥2 precision identical sensor nodes, or obtaining an array of sensor nodes intended for three-axis / two-axis measurements consisting of two shells and made exactly the same, with a given distribution in space, with n≥2 precision identical sensor nodes.

The essence of the technical solutions is illustrated by the following description and the accompanying drawings.

Figure 1 schematically shows the sensor nodes, their location in space relative to each other, made on the basis of solid-state curved shells, in particular cylindrical, for a magnetic field sensor based on the Hall effect: a) for biaxial measurements of the magnetic field - as a part of one shell with conventionally shown pairs of Hall contacts located on the inner surface of the shell, the azimuthal angle φ between them is 90 °; b) for two- and / or three-axis measurements of the magnetic field - in the composition of two shells perpendicular to each other relative to each other, with pairs of Hall contacts located on the inner surfaces of the shells conventionally shown, the azimuth angle between them is 90 °, which together determines orientation of pairs of Hall contacts in space at which the measured Hall stresses are orthogonal to the three components of the external magnetic field vector.

Figure 2 schematically shows a roll-up due to the action of built-in mechanical stresses of a pseudomorphic heterofilm from two forming layers when it is released from communication with the substrate.

Figure 3 shows the formation of two sensor nodes in a cylindrical shell based on A ₃ B ₅ semiconductor compounds with two pairs of Hall contacts (potential): a) a cross section of the original, in the particular case of a sensor, modulated doped quantum well heterostructure is schematically shown (QW) GaAs containing two-dimensional electron gas; b) schematically depicts a lithographically mesostructured planar multilayer heterostructure located on a substrate, with the formation of two pairs of Hall contacts (potential) and a pair of current contacts, between which there is a channel for current flow; c) a schematic representation of the formed cylindrical shell provided with ohmic contacts and current leads; d) a photographic image of a lithographically mesostructured planar multilayer heterostructure located on the substrate, with the formation of two pairs of Hall contacts (potential) and a pair of current contacts, between which there is a channel for current flow; f) a photographic image of a cylindrical shell equipped with ohmic contacts and current leads formed by folding a lithographically mesostructured flat multilayer heterostructure when it is released from communication with the substrate; where 1-6 pads.

Figure 4 presents a schematic representation of a magnetic field sensor based on the Hall effect for two- and / or three-axis measurements of a magnetic field in two shells sealed in a polymer.

Figure 5 presents the results of three-axis Hall measurements in an external magnetic field directed along the Z axis when the sample rotates around the X axis, with measured Hall voltages Ux, Uy and Uz proportional to the components of the magnetic field vector Bx, By and Bz.

Figure 6 schematically shows the contours of the forming layers of the multilayer film element, providing the implementation of directional bending of the film element when it is separated from the substrate by stimulating the etching process due to the presence of internal mechanical stresses at the window border: where 7 is the substrate; 8 - layer of GaAs; 9 - mechanically stressed InGaAs layer; 10 - sacrificial layer of AlAs.

The achievement of the specified technical result is based on the following features.

The active part of the sensor — the sensor nodes, in contrast to the known technical solutions presented above, is carried out directly in the multilayer shell (freed from communication with the substrate of a thin curved film), which contains, along with the forming layers, providing curvature due to the action of elastic stresses, functional layers — layers susceptible to magnetic field. The active part of the sensor (sensor nodes) has cross-shaped Hall elements (including pairs of Hall contacts) made with the possibility of their orientation in space by the corresponding mutually orthogonal components of the external magnetic field vector. Due to bending as a result of the presence of internal mechanical stresses in the film layers, the required orientation of the cross-shaped Hall elements located in the shell in space is achieved (see Figure 1). A layer that is susceptible to a magnetic field, or a system of layers that are collectively susceptible to a magnetic field, has the same curvature as the formative layers that bend under the influence of internal mechanical stresses when they are separated from the bond with the substrate. In this regard, the mesostructures, in particular, forming the Hall bridges, are also made in a curved configuration due to the bending of the film, while their configuration corresponds to the orientation of the cross-shaped Hall elements, in which the measured Hall stresses are orthogonal to the components of the external magnetic field vector (see Figure 1 ) The planes tangent to the shell at the centers of the cross-shaped Hall elements are orthogonal to each other due to the curvature of the shell. Moreover, these arrangements of elements relative to each other, in particular spatial, are set in a precise manner.

A layer that is susceptible to a magnetic field, or a system of layers that are collectively susceptible to a magnetic field, is a functional element of the sensor assembly and, in general, of the magnetic field sensor, plays a key role, since it provides the emergence of a Hall EMF. To measure the latter and determine the orthogonal components of the magnetic field in the sensor node, cross-shaped Hall elements with a spatial orientation corresponding to the determined orthogonal component of the external magnetic field are required. The last condition is satisfied due to the curvature provided by the forming layers.

Thus, on the one hand, the shell is a means of achieving the required orientation of the cross-shaped Hall elements in space, on the other hand, the shell is the place where the sensory nodes with the functional layer and Hall contacts are localized. The execution of the specified double function by the curved shell plays a key role in achieving the technical result. It is the implementation of the dual function of the solid-state curved shell, in contrast to the technical solutions discussed above, in which the shell performed only a single function, significantly simplifies the microstructuring of the solid-state heterostructure used to create the sensor, and eliminates the reasons that impede the achievement of the technical result.

The proposed magnetic field sensor is based on the method of folding thin strained films when they are released from communication with the substrate (V.Ya. Prinz, VASeleznev, A.K. Gutakovsky, AVChehovskiy, VVPreobrazenskii, MAPutyato, TAGavrilova. Free standing and overgrown InGaAs / GaAs nanotubes, nanohelical and their arrays. Physica E, 2000, v. 6, N 1-4, pp828-831). A strained two-layer film of materials with different lattice constants, when it is released from communication with the substrate, bends and rolls under the action of internal mechanical stresses (Figure 2). The elastic forces F ₁ and F ₂ in the forming layers — the compressed layer located on the sacrificial layer and the stretched layer located on the compressed layer — are directed in opposite directions and create a moment of forces M, which tends to bend the film. Until the sacrificial layer is etched, the film is rigidly bonded to the substrate by the sacrificial layer and held flat. With directed lateral etching of the sacrificial layer, the film from the forming layers begins to separate from the substrate. Under the action of the moment of elastic deformation forces, the film bends, acquiring a curvilinear shape corresponding to the minimum energy of internal stresses. The bend radius of curvature can be set with precision precision. It depends on the thickness of the film and the magnitude of the mechanical stresses in it. The radius is reproduced with precision accuracy, since it is determined by the relative mismatch of the periods of the crystal lattices of the materials that are chosen for the formation of the forming layers, and the thicknesses of the latter. By growing initial structures on the substrate with different thicknesses of epitaxial layers and compositions of solid solutions, it is possible to very accurately obtain the required value of the radius of curvature. The thickness during epitaxial growth is specified accurate to monoatomic layers. In the simplest case of a two-layer heterofilm with layer thicknesses d ₁ and d ₂ , mismatch of the lattice parameters of the layers Δа / а and Poisson's ratio v, the radius of curvature R is determined by the formula (M.Grundmann, Appl. Phys. Lett. 83, 2444 (2003)):

$$R=\frac{\mathrm{one}}{6}\frac{\mathrm{one}}{\raisebox{1ex}{$\Delta a$}\!\left/ \!\raisebox{-1ex}{$a$}\right.}\frac{{(d_{\mathrm{one}}+d_2)}^3}{(\mathrm{one}+\nu )d_{\mathrm{one}}{\mathrm{<figure-callout\; id="2"\; label="d"\; filenames="00000003.png,00000004.png"\; state="\{\{state\}\}">d</figure-callout>}}_2}$$

Thus, the local curvature of the shell is determined by the form-forming layers present in its composition, curved due to the action of elastic stresses. Forming layers are obtained at the stage of manufacturing on the substrate a multilayer film element - an element that is in a flat state and contains all the structural elements of the sensor node of the magnetic sensor, and more precisely, when a heterostructure is formed on the substrate. At the same stage, a functional layer is made as part of the heterostructure — a layer susceptible to a magnetic field, or a system of layers (as, for example, see Fig. 3, a)), which are collectively susceptible to a magnetic field, which are supplied in the future for the manufacture of the sensor Hall contacts (see Figure 3). The initial object during the formation of the film element is a solid multilayer film or heterostructure deposited on a solid substrate in any way, by molecular beam epitaxy, deposition from a liquid or gas phase, thermal or electron beam spraying. In the General case, the composition of the heterostructure perform a combination of layers of semiconductors, metals, dielectrics. The initial object meets the following requirements: firstly, a sufficient concentration of charge carriers must be ensured for the appearance of transverse (Hall) voltage due to the usual or abnormal (extraordinary) Hall effects during the flow of electric current in the film plane and the presence of an external magnetic field perpendicular to its plane ; secondly, there should be the possibility of local separation from the substrate; thirdly, there should be built-in mechanical stresses, under the influence of which, upon separation from the substrate, the solid multilayer film (heterostructure) bends and takes the required spatial configuration, in particular, due to the mismatch of the crystal lattice parameters with the layer materials.

The manufacture of a multilayer film element is carried out using materials, geometry and internal mechanical stresses that ensure orientation of the pairs of Hall contacts in space, at which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector, using the currently available arsenal of planar technology tools. To set the precision location of the sensor nodes among the planar technology methods, ensuring uniformity of the layer thickness and uniformity of mechanical stresses across the layer, such as epitaxy, electrochemical deposition, vacuum deposition, and other methods are used. Separating the film element from the substrate, they transform it under the action of internal mechanical stresses into a shell, the curvature of which can be varied over a wide range. The specific value of the shell curvature, which provides the required spatial arrangement of the pairs of Hall contacts, is set with high accuracy by the choice of the internal stresses of the forming layers, their thicknesses and the mechanical properties of the layers.

The manufacturing method allows the use of a wide range of materials for the structural layers of the sensor with a precise selection of their thicknesses and stresses, as well as the desired geometry of all sensor elements, including the exact spatial configuration. The first stage of the method consists in the formation of a film element, the contours of which are set lithographically, while on the substrate, one or more individual film elements are formed in a flat state. During the formation, the shape of the roll-up film element, the area of the beginning of its separation from the substrate and the roll-up, the roll-up direction are determined. Any type of lithography is used - optical, electronic, die for applying a protective mask of the desired shape to the surface of the original film and subsequent local removal of the film by etching (liquid, ion or other) to obtain the specified geometry of the multilayer film element. In areas of the film not protected by the mask, the film is completely removed. If necessary, the mask must be removed.

As part of a multilayer film element, at least two formative layers are grown with built-in mechanical stresses that create a moment of forces tending to bend the film. The thickness of each layer is selected from a few microns to one atomic monolayer, depending on the requirements of the sensor. In particular, a sequence of forming layers with built-in mechanical stresses can be performed with the possibility of setting a gradient of longitudinal mechanical stresses directed across the film. In addition, at least one functional layer is performed in the film element — a layer susceptible to a magnetic field, or a system of layers that are collectively susceptible to a magnetic field. Moreover, if the used material allows, the forming layer can act as a functional layer, thus combining two functions - ensuring curvature and creating a Hall EMF. At the same stage, after the manufacture of the forming and functional layer and obtaining the geometry of the multilayer film element, mesostructuring is carried out along the functional layer — cross-shaped Hall elements, current leads and contact pads are made (see Fig. 3, b), d)). In this case, they determine the shape of the conductive channels - current leads of the active region of the sensor and contact fields to relieve Hall voltage - contact pads. Any type of lithography is used - optical, electronic, die for applying a protective mask of the required shape to the surface of the original film and subsequent local removal of the film by etching (liquid, ion or other) to obtain the specified geometry of the conductors and contact pads. In non-masked areas of the film, the latter is removed to a depth sufficient for electrical isolation in the etching area. (Here, by electrical insulation should be understood a multiple, for example, 100 or more times, increase in the electrical resistance of the etched film compared to the original one.) In the presence of a sacrificial layer, etching is carried out until a depth is less than the depth of the sacrificial layer, avoiding exposure of the latter. After which the mask must be removed. At the same stage, the ohmic contacts of the sensor are formed by applying a layer of a suitable material, for example indium, or layers of several materials, for example germanium / nickel / gold, on the area of contact fields - contact pads 1-6 (see Figure 3). If necessary, after application, annealing is carried out in an inert atmosphere. Thus, at the first stage, all the structural elements of the magnetic field sensor are made; they are in a flat state because the mesostructured film is bonded to the substrate, in particular, due to the sacrificial layer present, if the latter is grown in the film element. However, the manufactured sensor is not yet ready for operation. It remains to give the flat structural elements the spatial arrangement required for measuring the orthogonal components of the external magnetic field (see Figure 3, c), e)).

In addition to the above-mentioned implementation of the first stage of the method, a variant is possible in which the production of a functional layer with current leads and contact pads is carried out in a single process using the Lift-off method (spraying on a mask with windows, followed by dissolving the mask material).

At the second stage of the manufacturing method, they proceed directly to operations related to obtaining a curved shell (tubes, scrolls, rolls) and the required location in the space of cross-shaped Hall elements, including pairs of Hall contacts. The created film element / elements are freed from bonding with the substrate by removing the underlying material below it / them or without removing the latter, using an action that releases the heterostructure from bonding with the substrate, for example, exposure to laser radiation. In the first case, the sacrificial layer previously grown on the substrate is etched. In this case, the multilayer film element is bent under the action of internal mechanical stresses of the forming layers and is transformed into a shell with a shape corresponding to the minimum energy of internal mechanical stresses. The bending of the film element in the desired direction is achieved using directional folding methods (A.V. Vorob'ev, V.Ya. Prinz. Directional rolling of strained heterofilms. Semiconductor Science and Technology, 17, 2002, pp614-616), based on anisotropy the elastic properties of the heterostructure layers, the etching anisotropy of the sacrificial layer, or through the use of certain configurations of the contours of the film element, which specify the desired direction of folding. In this case, the functional layer, cross-shaped Hall elements, current leads and, perhaps, in part even contact pads undergo transformation together with the forming layers of the multilayer film element.

In conclusion, they connect the wires, wires or other electrical leads to the pads 1-6 (see Figure 3).

We emphasize that the sequence of steps is the manufacture of the initial object in the form of a solid multilayer film or heterostructure, determining the shape of the multilayer film element, determining the shape of current leads and contact pads, forming at the last ohmic contacts, forming curvilinear shells, and finally, connecting electrical pads to the contact pads may differ from the sequence given here, depending on the means borrowed from the arsenal of planar technology for manufacturing Sensor Ia - materials and processing methods.

In the particular case of the implementation of the proposed technical solution, the resulting shell with a functional layer, cruciform Hall elements with pairs of Hall contacts can be transferred to another carrier element or placed in a different environment. In particular, it can be sealed in a polymer (see Figure 4).

The design of the sensor with a shell / shells with sensor assemblies is subject to mechanical stress. In order to avoid the devastating effects of exposure and disabling the sensor, it is recommended that the manufactured sensor design be placed in a solid matrix. To do this, in the region of the supporting structural element (substrate) of the sensor with shells, a liquid polymer is applied with its subsequent curing. Such sealing can be performed using polydimethylsiloxane, an organosilicon polymer. Polydimethylsiloxanes are characterized by chemical inertness, low surface tension, water repellent and dielectric properties. In addition, they are transparent, which allows you to control the state of the structure using an optical microscope.

Note that the radius of curvature of the resulting shell depends on the thickness and mechanical properties of all layers of the mesostructured heterostructure. The formation at the first stage of a functional layer with a large thickness will lead to a significant increase in the radius of curvature. The presence of forming layers with built-in mechanical stresses in the composition of a multilayer shell with a thickness from hundreds of micrometers to a few nanometers that specify the local curvature of the shell determines its characteristic scale. Varying the local curvature by selecting the parameters of the forming and functional layers provides the ability to scale the magnetic field sensor.

The manufacturing method provides a wide range of sizes of active sensor elements (from units of nanometers to units of millimeters) and their spatial configurations. Shells through the operations of the proposed method, based on planar technology and the principles of transformation of film elements into shells, can be made of various geometric shapes and sizes, with the possibility of ensuring the required positioning in the space of Hall elements. In the case of performing a magnetic field sensor using more than one shell, the method allows them to be implemented, in the general case, in different shapes, orientations, and sizes, and to provide their desired placement relative to each other.

In the above works of L. Sileo and M. Todaro and colleagues, the height of the cantilever structures above the substrate reaches approximately 400 μm, which is unacceptable a lot both from the point of view of manufacturing micro and Hall nanosensors, and from the point of view of the resistance of cantilever structures to mechanical stresses, in particular, to the action of capillary forces during the manufacturing and / or operation of the sensor. This size cannot be significantly reduced (by 2–3 orders of magnitude) due to the fundamental limitations of the used microstructuring option, known as “microorigami”. On the contrary, the diameter of the cylindrical shells with sensor nodes (i.e., the size of the sensor in the direction perpendicular to the substrate) is tens of micrometers and can be scaled to the submicron and nanoscale region by appropriate selection of the thickness and composition of the strained thin film from which the shells are formed. It is known from the literature that to date the minimum achieved diameter of cylindrical shells is 2 nm (V.Ya. Prinz, VASeleznev, A.K. Gutakovsky, AVChehovskiy, VVPreobrazenskii, M.A. Putyato, TAGavrilova. Free standing and overgrown InGaAs / GaAs nanotubes, nanohelical and their arrays. Physica E, 2000, v.6, N 1-4, pp828-831), while the minimum known height of the microorigami structures is about 50 μm (POVaccaro et al., Appl. Phys. Lett. 78, 2852 (2001)).

With regard to materials, the proposed method allows the use of a wide range of materials both for structural layers of the shell and other structural elements (for example, a supporting element in the case of transfer of the shell from the substrate).

In the manufacture of the sensor, operations borrowed from the arsenal of planar technology provide high structural excellence of the internal structure of the forming and functional layers and other structural layers. High internal perfection of the forming layers is a guarantee of the accuracy of setting the local curvature of the multilayer shell. The perfection factor of the internal structure of the structural layers determines the reproducibility of the sensor characteristics.

The presence of formative layers that accurately determine the curvature of the shell by appropriate selection of their thicknesses and internal mechanical stresses, as well as methods of planar technology for reproducing patterns of layers of the film element during mesostructure of the heterostructure, provide high reproducibility of the shell shape. The ability to accurately position the film elements relative to each other, provided by planar technology, allows for the highly reproducible preset placement of finished shells.

The increase in the strength of the sensor structures is a direct result of the implementation of the active elements of the sensor in the shell, held by the internal mechanical stresses of the forming layers, and the perfection of the internal structure of the shell, which provides high strength and dimensional stability of the active sensor elements - sensor nodes.

Thus, it is shown above how the design and manufacturing features of the sensor affect the achievement of a technical result, ensuring the accuracy and reliability of simultaneous measurements of the orthogonal components of the magnetic field, as well as the components of the magnetic field vector other than perpendicular to the plane of the sensor, increasing the reliability of the sensor and reproducibility of parameters sensors.

Using methods and materials of the traditional technology for the production of integrated circuits (ICs) allows the integration of the sensor with the IC.

In the General case, the implementation of the magnetic field sensor contains sensor nodes, implemented using the Hall effect, while the sensor nodes with Hall contacts are made as part of a curved shell (see Figure 1). The curvilinear shell is formed by a system of layers, among which are susceptible to magnetic fields - functional and shape-forming. The latter due to the action of mechanical stresses provided the curvature of the shell and the possibility of orienting the cross-shaped Hall elements of the sensor nodes in space with the compliance of the measured Hall stresses with the orthogonal components of the external magnetic field vector (see Figure 1).

In the particular case of the sensor implementation, the sensor nodes are made up of two shells (see Fig. 1, b)) for triaxial / biaxial measurements. The shells are made of cylindrical shape and are located relative to each other so that their generators are perpendicular to each other. Each shell is equipped with sensor nodes with cross-shaped Hall elements, including Hall contacts, oriented in space with matching the measured Hall stresses to the three orthogonal components of the external magnetic field vector. The azimuthal angle between the pairs of Hall contacts of the shells is 90 °, which determines the required orientation of the pairs of Hall contacts in space for three- or biaxial measurements of the magnetic field vector.

In the particular case of the implementation of the sensor, the sensor nodes are made up of a single shell (see Figure 1, a)) for biaxial measurements. Sensor nodes are made for biaxial measurements as part of a single shell. The shell is made of a cylindrical shape with pairs of Hall contacts of the cross-shaped Hall elements of sensor nodes oriented in space with the correspondence of the measured Hall stresses to the two orthogonal components of the external magnetic field vector. The azimuthal angle φ between pairs of Hall contacts, due to which the measured Hall stresses correspond to two orthogonal components of the external magnetic field vector, is 90 °.

Each sensor node is designed to determine its orthogonal component of the external magnetic field vector and includes a shape-forming and functional layers, a cross-shaped Hall element based on the functional layer, and Hall contacts with a pair of potential contacts. In the shell (see Figure 1), two sensor nodes are made.

In the particular case of implementation, the sensor is made as part of the above-mentioned array of sensor nodes in two shells (see Fig. 1, b)) - for three-axis / biaxial measurements or sensor nodes in one shell (see Figure 1, a)) - for biaxial measurements. In this case, the sensor nodes in the amount of n≥2 are formed exactly the same, with a given distribution in space. This case of the sensor makes it possible to measure the magnetic field gradient, including the time dependence of the magnetic field gradient. By making shells with sensor nodes exactly the same, the signal-to-noise ratio improves.

The shell, in particular, is located on the substrate (see Figure 1, see Figure 3, c)). As the substrate, a GaAs substrate is used. The shell may be open - with an open cylindrical surface. A sacrificial layer is present on the substrate, due to which the shell is connected with the substrate. The sacrificial layer on a GaAs substrate is made of AlAs. The wall thickness of the shell is approximately from (5 ÷ 6) × 10 ^-10 to about 10 ^-5 m.

The forming layers are made of pseudomorphic single crystal from materials characterized in the free state by different periods of the crystal lattice. For forming layers located on the outside of the shell, materials are used that are characterized in the free state by a large period of the crystal lattice. In particular, the forming layers are made using GaAs and InGaAs materials. In the particular case of the implementation of the magnetic field sensor in the system of layers, including functional and shape-sensitive magnetic fields, the shape-forming layer is made susceptible to the magnetic field, for example, from GaAs or FePt (the latter - in the case of the implementation of an anomalous, extraordinary effect in the magnetic field sensor Hall). A magnetic field susceptible layer is a functional layer and satisfies the following requirements. Physical properties, for example, the concentration and mobility of charge carriers, a functional layer provide the appearance of a transverse (Hall) voltage during the flow of electric current in this layer and in the presence of an external magnetic field perpendicular to its surface. The functional layer is made of uniformly or modulated alloyed semiconductor, metal or a combination of these materials. In this case, a uniformly or modulated doped heterostructure can be used.

In an alternative embodiment of the sensor, in order to increase its sensitivity, a quantum well with an electron gas is formed in the system of layers that are susceptible to the magnetic field — functional and shape-forming, see FIG. 3, a), which is a 13 nm thick GaAs layer. The concentration of electron gas in a quantum well is about 10 ¹¹ cm ^-2 . The indicated quantum well is located between the layers of the AlGaAs solid solution doped with Si. Layers in the AlGaAs sequence are the barrier, GaAs are the quantum well, AlGaAs are the barrier located in the shell between the layer of GaAs made on the side of the inner volume of the shell, which is a protective layer, and the forming layer located on the outside of the shell made of InGaAs (see Figure 3, a)). Layers of AlGaAs solid solution with a larger band gap than that of a GaAs quantum well are barrier layers and provide the presence of an electron gas in the quantum well in the required concentration. With respect to the barrier layers, δ doping of Si was performed. The GaAs layer, made on the side of the inner volume of the shell, is a “sar” layer that performs a protective function. A similar system of layers from a quantum well and barriers, collectively susceptible to a magnetic field, is used as a functional layer — a layer susceptible to a magnetic field, in the above analogs. As in the proposed particular case of the solution, in analogues the specified system of layers is equipped with a protective "sar" layer.

Two sensor nodes are made in the wall of the shell of a cylindrical shape, mesostructures are lithographically formed on the inside of the shell with the formation of cross-shaped Hall elements - Hall bridges (see Fig. 3, b), c), d)). The channel for passing current of the cruciform Hall element of the sensor node — the channel of the Hall bridge is located along the guide cylindrical surface of the shell. Moreover, in the sensor nodes along the channel, two pairs of Hall contacts are made for measuring Hall voltage — potential contacts (see Figure 1). In each pair, contacts are located on opposite sides of the channel. The azimuthal angle between the pairs of contacts is 90 ° (see Figure 1). Each Hall pair is designed to determine one of the components of the external magnetic field vector. A channel common to two sensor nodes is made by connecting current contacts common to two sensor nodes. The length of the common channel is πR / 2 and more, R is the radius of curvature of the shell. In the case of a sensor operating on the basis of the ordinary Hall effect, the functional layer that is susceptible to the magnetic field, as well as the forming layer, is made of a cylindrical shape, in it the geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads (see Figure 3) . From current and potential contacts of the Hall bridges by lithography and subsequent deposition of the corresponding material - Au, current leads are laid to the contact pads located on the substrate, with ohmic contacts to the functional layer, which are made of a germanium / nickel / gold layer, followed by annealing. In the case of a sensor operating on the basis of an extraordinary Hall effect, a functional layer susceptible to a magnetic field is made, in contrast to the formative layer, having a pattern in the form of two connected cross-shaped elements, which determines the geometry of the Hall bridge. The functional layer was obtained by preliminary applying a protective resist to the forming layer and forming in the resist a through window with a pattern in the form of two connected cross-shaped elements, followed by spraying into the FePt window and final, after spraying, removing the protective resist. In this case, the functional layer, like the forming layer, has curvature. In this case, ohmic contacts to the functional layer can be made directly at the protrusions of the Hall element - the Hall bridge, either on the contact pads, or between them at any point in the current leads. The conductors are also made by lithography and the subsequent deposition of the corresponding material - Au and laid to the contact pads located on the substrate and also made of gold. To obtain an ohmic contact, it is important that the layers of FePt and Au overlap. If ohmic contacts are performed at the protrusions of the Hall bridge, then the place in which the layers are overlapped is located at the protrusions. If ohmic contacts are performed at the contact pads, the current guide regions cover FePt; in the region of the contact pads, the FePt and Au layers overlap. If the ohmic contacts are located at the point of the current leads, then the overlapping of these layers is performed at this point.

In the particular case of implementation, the sensor is additionally equipped with signal processing circuits formed on the same substrate, on which a shell with sensor nodes is located.

In the particular case of the implementation of the sensor, the sensor nodes are made up of a curved shell, which is sealed in a solid matrix of non-magnetic material (see Figure 4). For example, a curved shell is sealed in a polymer.

The magnetic field sensor operates as follows.

The principle of operation of the proposed magnetic field sensor is based on the Hall effect, which can be either ordinary (ordinary) (RSPopovic "Hall Effect Devices", IOP Publishing (2004)), or abnormal (extraordinary) (N. Nagaosa et al., Rev Mod. Phys. 82, 1539 (2010)). The Hall effect in one and the other cases consists in the appearance of a transverse potential difference — the Hall voltage — when a DC conductor is placed in a magnetic field. The potential difference arises in the direction perpendicular to the magnetic induction vector and the current direction, and is proportional to the component of the magnetic induction vector normal to the surface (in the case of an anomalous Hall effect, the linear dependence of the Hall EMF on the external field is observed only in a limited range of magnetic fields, which determine the working range of the corresponding Hall sensor).

The active part of the sensor (sensor nodes) is a conductive curved shell with cross-shaped Hall elements arranged so that the Hall voltages measured on them correspond to the orthogonal components of the external magnetic field vector. In particular, it can be a cylindrical shell, in the wall of which mesostructures are made with the formation of Hall bridges with current and potential contacts and current leads from them to contact pads 1-6 (see Figure 3) - external electrical contacts. The azimuthal angle φ between the pairs of Hall contacts is 90 ° (see Figure 1). In the presence of an external magnetic field B and the passage of current along the channel of the Hall bridge located along the guide cylindrical surface (as shown in Fig. 1), on both pairs of Hall contacts located along the channel on its opposite sides, a Hall EMF proportional to the local normal value to the surface of the magnetic field component. Thus, by measuring the Hall EMF values on two pairs of contacts, two orthogonal components of the magnetic field vector are determined. For three-axis measurements, a third sensor assembly is connected, made up of a second curved shell, in particular a second cylindrical shell, the generatrix of which is perpendicular to the generatrix of the first curved shell, the plane tangent to the surface of the second shell in the center of the cross-shaped Hall element of the third sensor assembly, perpendicular to the planes, tangent to the surface of the first shell in the centers of the cross-shaped Hall elements of the first and second sensory nodes (see Figure 1, b)). In the presence of an external magnetic field B and the passage of current along the channels of the Hall bridges located along the guiding cylindrical surfaces of the shells (as shown in Fig. 1), Hall EMFs are proportional to the local values of the magnetic field component normal to the surface on all three pairs of Hall contacts. Thus, by measuring the Hall EMF values on three pairs of potential contacts, three orthogonal components of the magnetic field vector are determined.

The obtained experimental data (Figure 5) of the angular dependences of the Hall resistance clearly demonstrate the possibility of three-axis measurements of the external magnetic field using the proposed sensor. The geometry of the experiment in triaxial measurements is shown in Fig. 1, b. The external magnetic field is directed along the Z axis. The Hall stresses Ux, Uy, and Uz, proportional to the components of the magnetic field vector Bx, By, and Bz, respectively, are measured when the sample rotates around the X axis. Figure 5 shows the dependences of Ux, Uy, and Uz on the angle turning ψ. Dependencies Uy (ψ) and Uz (ψ) are sinusoids of approximately equal amplitude, phase shifted by 90 °, which proves the orthogonal orientation of the corresponding sensor nodes. At the same time, the Hall voltage Ux is practically independent of the rotation angle ψ, i.e., the external magnetic field vector lies with good accuracy in the plane of the corresponding sensor node. Thus, the measurement results shown in FIG. 5 demonstrate the operation of a triaxial Hall sensor based on cylindrical shells.

As information confirming the possibility of implementing the method with the achievement of a technical result, we give the following examples of its implementation.

Example 1

A multilayer film element is formed on a GaAs semi-insulating substrate with a (100) orientation (see FIG. 3). Materials, geometry, and internal mechanical stresses are chosen to ensure orientation of the cross-shaped Hall elements of the sensor nodes with Hall contacts in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. At the stage of formation of the film element, layers are formed that are forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts and conductors, layers of contact pads. Preliminarily, a pseudomorphic AlAs sacrificial layer 10 nm thick is formed on the substrate. In the manufacture of a multilayer film element, a shape-forming, mechanically stressed (compressed) layer of InGaAs is grown, and the second shape-forming layer is made in the form of a system of GaAs and AlGaAs layers, which simultaneously plays the role of a functional layer that is susceptible to a magnetic field with Hall contacts and current leads. A 13-nm-thick GaAs quantum well is formed in the layer system with an electron gas with an electron concentration of about 10 ¹¹ cm ^-2 . A quantum well is placed between the layers of the AlGaAs solid solution doped with SL. Moreover, the layers in the AlGaAs sequence are the layer corresponding to the barrier, the GaAs layer corresponding to the quantum well, the AlGaAs layer corresponding to the barrier is located between the GaAs layer, which is the protective layer, and the forming layer located on a sacrificial layer grown on a substrate and made of InGaAs. The thickness of the multilayer film element is set equal to 100 nm. Forming and functional layers are formed by molecular beam epitaxy, observing the conditions of pseudomorphic growth, from these materials as having different lattice constants and capable of generating a transverse (Hall) voltage when an electric current flows in the plane of the layers and there is an external magnetic field perpendicular to their plane, due to the usual Hall effect (RSPopovic "Hall Effect Devices", IOP Publishing (2004)). The layer of contact pads, providing ohmic contact to the functional layer, is formed by sequential deposition of germanium (Ge), nickel (Ni) and gold (Au), followed by annealing. Drawings of layers, including drawings defining the contours of the film element, drawings of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from the latter to contact pads, contact pads are set using planar technology - lithographically.

The direction of bending of the multilayer film element during subsequent separation from the substrate is set during its formation, by setting patterns of layers, including a pattern defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from last to contact pads, drawings of contact pads. First, drawings are formed that define the contours of the film element — the contours of the formative and functional layers in the form of windows in layers depth to the sacrificial layer. For etching windows, an orthophosphoric acid based etchant (H ₃ PO ₄ : H ₂ O ₂ : H ₂ O / 3: 1: 50) is used. Then, the final part of the pattern formation is carried out, defining the cross-shaped Hall element of the sensor assembly, making the areas of current leads and contact pads, using the same etching agent for etching windows. When forming a multilayer film element, a drawing of a functional layer that is susceptible to a magnetic field, corresponding to two sensor nodes with Hall contacts, with current leads from the latter to the contact pads, is formed with a channel for transmitting current common to the two sensor nodes, lying in the direction of the film element bending, with a length channel at least πR / 2, R is the radius of curvature of the shell. At the same time, two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage — potential contacts. Contacts are placed along the channel on opposite sides of it. The azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs is πR / 2, R is the radius of curvature of the shell. Each pair is designed to determine its orthogonal component of the external magnetic field. A drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads, and the drawing of the contact pads themselves are formed lithographically by defining the shape of the cross-shaped Hall element, current leads and contact pads. The geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads. From current and potential contacts of Hall bridges by lithography and subsequent deposition of Au, conductors are laid to the contact pads located on the substrate, with ohmic contacts to the functional layer. Lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. To obtain ohmic contacts, germanium, nickel and gold are sequentially sprayed on the area of the contact areas specified by the figure, and annealed in a hydrogen atmosphere at a temperature of 450 ° C for 5 minutes.

Then the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into the shell with the orientation of the pairs of Hall contacts in space being achieved, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. To separate the film element from the substrate, the material of the element located under the film element, the material of the AlAs sacrificial layer, is removed, providing directional bending of the film element with the formation of a cylindrical shell. The required direction of bending of the film element is achieved by directional etching — selective lateral (lateral) etching of the sacrificial layer in the direction due to the anisotropy of the mechanical properties of the film element and its lithographic pattern. Poison the sacrificial layer in the etchant based on hydrofluoric acid (HF: H ₂ O / 1: 10). The etching of the sacrificial layer is carried out before the separation of the film element within the area on which the sensor nodes are located (see Figure 3). Thus, a part of the initially flat film element is transformed into a cylindrical shell, while the contact pads 1-6 with ohmic contacts are placed on the substrate, leaving them rigidly connected to the substrate due to the timely termination of lateral etching of the sacrificial layer. As a result of the transformation of the film element into a cylindrical-shaped shell, a channel for transmitting current is placed along the guide of the cylindrical shell, Hall contacts for measuring Hall voltage are placed along the channel on opposite sides of it, and the azimuth angle between pairs of Hall contacts is maintained at 90 °. In this case, the contact pads with ohmic contacts are placed on the substrate and are rigidly connected with it. In the final, the shell is placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shell and cured (see Figure 4). Before sealing the shell into the polymer, the formed structure is placed in ethyl acetate, which is a solvent of polydimethylsiloxane, and then transferred to unpolymerized polydimethylsiloxane. Substitution of ethyl ether inside the shell, as well as coating the surface of the shell from the outside. To polymerize polydimethylsiloxane and seal the structure into a polymer, it is heated in an oven at a temperature of 90 ° C for 3 hours.

Example 2

A multilayer film element is formed on a GaAs semi-insulating substrate with a (100) orientation (see FIG. 3). Materials, geometry, and internal mechanical stresses are chosen to ensure orientation of the cross-shaped Hall elements of the sensor nodes with Hall contacts in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. At the stage of formation of the film element, layers are formed that are forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts and conductors, layers of contact pads. Preliminarily, a pseudomorphic AlAs sacrificial layer 10 nm thick is formed on the substrate. In the manufacture of a multilayer film element, a forming, mechanically stressed (compressed) layer is grown from InGaAs and a second forming layer from GaAs, which are both functional and magnetic-susceptible layers. The InGaAs and GaAs layers are uniformly doped with silicon (Si) until the concentration of electrically active donors reaches 5 × 10 ¹⁸ cm ^-3 . The thickness of the multilayer film element is set equal to 50 nm. Forming and functional layers are formed by molecular beam epitaxy, observing the conditions of pseudomorphic growth, from these materials as having various lattice constants and capable of generating a transverse (Hall) voltage when an electric current flows in the plane of the layers and there is an external magnetic field perpendicular to their plane, due to the usual Hall effect (RSPopovic "Hall Effect Devices", IOP Publishing (2004)). The layer of contact pads, providing ohmic contact to the functional layer, is formed by sequential deposition of germanium (Ge), nickel (Ni) and gold (Au), followed by annealing. Drawings of layers, including drawings defining the contours of the film element, drawings of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from the latter to contact pads, contact pads are set using planar technology - lithographically.

The direction of bending of the multilayer film element during subsequent separation from the substrate is set during its formation, by setting patterns of layers, including a pattern defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from last to contact pads, drawings of contact pads. First, drawings are formed that define the contours of the film element — the contours of the formative and functional layers in the form of through windows in the layers to the sacrificial layer. For etching windows, an orthophosphoric acid based etchant (H ₃ PO ₄ : H ₂ O ₂ : H ₂ O / 3: 1: 50) is used. Then, the final part of the pattern formation is carried out, defining the cross-shaped Hall element of the sensor assembly, making the areas of current leads and contact pads, using the same etching agent for etching windows. When forming a multilayer film element, a drawing of a functional layer that is susceptible to a magnetic field, corresponding to two sensor nodes with Hall contacts, with current leads from the latter to the contact pads, is formed with a channel for transmitting current common to the two sensor nodes, lying in the direction of the film element bending, with a length channel at least πR / 2, R is the radius of curvature of the shell. At the same time, two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage — potential contacts. Contacts are placed along the channel on opposite sides of it. The azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs is πR / 2, R is the radius of curvature of the shell. Each pair is designed to determine its orthogonal component of the external magnetic field. A drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads, and the drawing of the contact pads themselves are formed lithographically by defining the shape of the cross-shaped Hall element, current leads and contact pads. The geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads. From current and potential contacts of Hall bridges by lithography and subsequent deposition of Au, conductors are laid to the contact pads located on the substrate, with ohmic contacts to the functional layer. Lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. To obtain ohmic contacts, germanium, nickel and gold are sequentially sprayed on the area of the contact areas specified by the figure, and annealed in a hydrogen atmosphere at a temperature of 450 ° C for 5 minutes.

Then the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into the shell with the orientation of the pairs of Hall contacts in space being achieved, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. To separate the film element from the substrate, the material of the element located under the film element, the material of the AlAs sacrificial layer, is removed, providing directional bending of the film element with the formation of a cylindrical shell. The required direction of bending of the film element is achieved by directional etching — selective lateral (lateral) etching of the sacrificial layer in the direction due to the anisotropy of the mechanical properties of the film element and its lithographic pattern. Poison the sacrificial layer in the etchant based on hydrofluoric acid (HF: H ₂ O / 1: 10). The etching of the sacrificial layer is carried out before the separation of the film element within the area on which the sensor nodes are located (see Figure 3). Thus, a part of the initially flat film element is transformed into a cylindrical shell, while the contact pads 1-6 with ohmic contacts are placed on the substrate, leaving them rigidly connected to the substrate due to the timely termination of lateral etching of the sacrificial layer. As a result of the transformation of the film element into a cylindrical-shaped shell, a channel for transmitting current is placed along the guide of the cylindrical shell, Hall contacts for measuring Hall voltage are placed along the channel on different sides of it, and the azimuth angle between pairs of Hall contacts is maintained at 90 °. In this case, the contact pads with ohmic contacts are placed on the substrate and are rigidly connected with it. In the final, the shell is placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shell and cured (see Figure 4). Before sealing the shell into the polymer, the formed structure is placed in ethyl acetate, which is a solvent of polydimethylsiloxane, and then transferred to unpolymerized polydimethylsiloxane. Substitution of ethyl ether inside the shell, as well as coating the surface of the shell from the outside. To polymerize polydimethylsiloxane and seal the structure into a polymer, it is heated in an oven at a temperature of 90 ° C for 3 hours.

Example 3

A multilayer film element is formed on a GaAs semi-insulating substrate with a (100) orientation (see FIG. 3). Materials, geometry, and internal mechanical stresses are chosen to ensure orientation of the cross-shaped Hall elements of the sensor nodes with Hall contacts in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. At the stage of formation of the film element, layers are formed that are forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts and conductors, layers of contact pads. Preliminarily, a pseudomorphic AlAs sacrificial layer 10 nm thick is formed on the substrate. In the manufacture of a multilayer film element, forming layers of undoped InGaAs and GaAs with a total thickness of 2 nm are grown. A layer of FePt 2 nm thick is placed on them as a functional layer susceptible to a magnetic field. The thickness of the multilayer film element is set equal to 4 nm. Forming layers are formed by molecular beam epitaxy, observing the conditions of pseudomorphic growth, from these materials as having different lattice constants. The functional layer is formed by sputtering as capable of causing transverse (Hall) stress during electric current flow in the plane of the layers and the presence of an external magnetic field perpendicular to their plane due to the anomalous Hall effect (N. Nagaosa et al., Rev. Mod. Phys. 82 1539 (2010)). A layer of contact pads providing ohmic contact to the functional layer is formed from gold by sputtering. Drawings of layers, including drawings defining the contours of the film element, drawings of forming, mechanically stressed, and functional, susceptible to a magnetic field, layers with Hall contacts with current leads from the latter to contact pads, contact pads are set using planar technology - lithographically.

The direction of bending of the multilayer film element during subsequent separation from the substrate is set during its formation, by setting patterns of layers, including a pattern defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from last to contact pads, drawings of contact pads. First, drawings are formed that define the contours of the film element — the contours of the forming elements in the form of through windows in layers to the sacrificial layer. For etching windows, an orthophosphoric acid based etchant (H ₃ PO ₄ : H ₂ O ₂ : H ₂ O / 3: 1: 50) is used. Then, the final part of the pattern formation is carried out, defining the cross-shaped Hall element of the sensor assembly, making the areas of current leads and contact pads, using the same etching agent for etching windows. First, a layer of gold is formed by sputtering through a resist mask, prepared lithographically, on the area of contact pads and current leads. Then, by spraying through a resist mask, prepared by lithographic methods, a functional layer of FePt is formed in the form of a cross-shaped Hall element (Hall bridge) with current leads, moreover, in the area of current conductors, FePt partially overlaps the areas of current leads covered with gold, which ensures ohmic contact between each contact area and a functional layer. Thus, ohmic contacts get directly to the functional layer, directly at the protrusions of the Hall element - the Hall bridge. When forming a multilayer film element, a drawing of a functional layer that is susceptible to a magnetic field, corresponding to two sensor nodes with Hall contacts, with current leads from the latter to the contact pads, is formed with a channel for transmitting current common to the two sensor nodes, lying in the direction of the film element bending, with a length channel at least πR / 2, R is the radius of curvature of the shell. At the same time, two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage — potential contacts. Contacts are placed along the channel on opposite sides of it. The azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs is πR / 2, R is the radius of curvature of the shell. Each pair is designed to determine its orthogonal component of the external magnetic field. A drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads, and the drawing of the contact pads themselves are formed lithographically by defining the shape of the cross-shaped Hall element, current leads and contact pads. Lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. Gold is sprayed onto the area of the contact areas specified by the pattern.

Then the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into the shell with the orientation of the pairs of Hall contacts in space being achieved, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. To separate the film element from the substrate, the material of the element located under the film element, the material of the AlAs sacrificial layer, is removed, providing directional bending of the film element with the formation of a cylindrical shell. The required direction of bending of the film element is achieved by directional etching — selective lateral (lateral) etching of the sacrificial layer in the direction due to the anisotropy of the mechanical properties of the film element and its lithographic pattern. Poison the sacrificial layer in the etchant based on hydrofluoric acid (HF: H ₂ O / 1: 10). Etching of the sacrificial layer is carried out before the separation of the film element within the area on which the sensor nodes are located. Thus, part of the initially planar film element is transformed into a cylindrical shell, while the contact pads 1-6 are placed on the substrate, leaving them rigidly connected to the substrate due to the timely termination of lateral etching of the sacrificial layer. As a result of the transformation of the film element into a cylindrical-shaped shell, a channel for transmitting current is placed along the guide of the cylindrical shell, Hall contacts for measuring Hall voltage are placed along the channel on opposite sides of it, and the azimuth angle between pairs of Hall contacts is maintained at 90 °. In this case, the contact pads are placed on the substrate and are rigidly connected with it.

Example 4

On a GaAs semi-insulating substrate with an orientation of (100), multilayer film elements are formed (see FIG. 3) in the amount of two elements. Materials, geometry, and internal mechanical stresses are chosen to ensure orientation of the cross-shaped Hall elements of the sensor nodes with Hall contacts in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. At the stage of formation of the film elements, layers are formed that are forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts and conductors, layers of contact pads. Preliminarily, a pseudomorphic AlAs sacrificial layer 10 nm thick is formed on the substrate. In the manufacture of multilayer film elements, a shape-forming, mechanically stressed (compressed) layer of InGaAs is grown, and the second shape-forming layer is made in the form of a system of GaAs and AlGaAs layers, which simultaneously plays the role of a functional layer that is sensitive to a magnetic field with Hall contacts and current leads. A 13-nm-thick GaAs quantum well is formed in the layer system with an electron gas with an electron concentration of about 10 ¹¹ cm ^-2 . A quantum well is located between the layers of AlGaAs solid solution doped with SL. Moreover, the layers in the AlGaAs sequence a layer corresponding to a barrier, a GaAs layer corresponding to a quantum well, an AlGaAs layer corresponding to a barrier are arranged between a GaAs layer, which is a protective layer, and a forming layer located on a sacrificial layer grown on a substrate and made of InGaAs . The thickness of each multilayer film element is set equal to 100 nm. Forming and functional layers are formed by molecular beam epitaxy, observing the conditions of pseudomorphic growth, from these materials as having different lattice constants and capable of generating a transverse (Hall) voltage when an electric current flows in the plane of the layers and there is an external magnetic field perpendicular to their plane, due to the usual Hall effect (RSPopovic "Hall Effect Devices", IOP Publishing (2004)). The layer of contact pads, providing ohmic contact to the functional layer, is formed by sequential deposition of germanium (Ge), nickel (Ni) and gold (Au), followed by annealing. Drawings of layers, including drawings defining the contours of the film element, drawings of forming, mechanically stressed and functional, susceptible to a magnetic field, layers with Hall contacts with current leads from the latter to contact pads, contact pads are set using planar technology - lithographically.

The direction of bending of each multilayer film element during subsequent separation from the substrate is set during its formation by setting patterns of layers, including a pattern defining the contours of the film element, patterns of forming, mechanically strained, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from the latter to pads, drawings of pads. First, drawings are formed that define the contours of each film element — the contours of the formative and functional layers in the form of through windows in the layers to the sacrificial layer. For etching windows, an orthophosphoric acid based etchant (H ₃ PO ₄ : H ₂ O ₂ : H ₂ O / 3: 1: 50) is used. Then, the final part of the pattern formation is carried out, defining the cross-shaped Hall element of the sensor assembly, making the areas of current leads and contact pads, using the same etching agent for etching windows. During the formation of each multilayer film element, a drawing of a functional layer that is susceptible to a magnetic field, corresponding to two sensor nodes with Hall contacts, with current leads from the latter to the contact pads, is formed with a channel for transmitting current common to the two sensor nodes, lying in the direction of the film element bending, with a channel length of at least πR / 2, R is the radius of curvature of the shell. At the same time, two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage — potential contacts. Contacts are placed along the channel on opposite sides of it. The azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs is πR / 2, R is the radius of curvature of the shell. Each pair is designed to determine its orthogonal component of the external magnetic field. A drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads, and the drawing of the contact pads themselves are formed lithographically by defining the shape of the cross-shaped Hall element, current leads and contact pads. The geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads. From current and potential contacts of Hall bridges by lithography and subsequent deposition of Au, conductors are laid to the contact pads located on the substrate, with ohmic contacts to the functional layer. Lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. To obtain ohmic contacts, germanium, nickel and gold are sequentially sprayed on the area of the contact areas specified by the figure, and annealed in a hydrogen atmosphere at a temperature of 450 ° C for 5 minutes. When forming two multilayer film elements, their patterns are realized with the possibility of perpendicular directions of bending and obtaining shells of a cylindrical shape, the forms of which are perpendicular. For this, the layer patterns of the first film element are repeated in the second film element with a rotation of 90 °.

Then, both film elements are separated from the substrate, transforming them under the action of internal mechanical stresses into shells with the orientation of the pairs of Hall contacts in space being achieved, in which the measured Hall stresses correspond to the three orthogonal components of the external magnetic field vector. To separate both film elements from the substrate, the material of the element located under the film elements, the material of the AlAs sacrificial layer, is removed, providing directional bending of each film element with the formation of a cylindrical shell. The required direction of bending of each film element is achieved by directional etching — selective lateral (lateral) etching of the sacrificial layer in the direction due to the anisotropy of the mechanical properties of the film element and its lithographic pattern. Poison the sacrificial layer in the etchant based on hydrofluoric acid (HF: H ₂ O / 1: 10). The etching of the sacrificial layer is carried out before the separation of each film element within the area on which the sensor nodes are located (see Figure 3). Thus, parts of the initially two flat film elements are transformed into cylindrical shells, while contact pads 1-6 with ohmic contacts are placed on the substrate, leaving them rigidly connected to the substrate due to the timely termination of lateral etching of the sacrificial layer. As a result of the transformation of each film element into a cylindrical shell, a channel for transmitting current is placed along the guide of the cylindrical shell, Hall contacts for measuring Hall voltage are placed along the channel on different sides of it, and the azimuth angle between pairs of Hall contacts is maintained at 90 °. In this case, the contact pads with ohmic contacts are placed on the substrate and are rigidly connected with it. In the final, the shells are placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shells and cured (see FIG. 4). Before sealing the shells into the polymer, the formed structure is placed in ethyl acetate, which is a solvent of polydimethylsiloxane, and then transferred to unpolymerized polydimethylsiloxane. Substitution of ethyl ether inside the shells is carried out, as well as coating the surface of the shells from the outside. To polymerize polydimethylsiloxane and seal the structure into a polymer, it is heated in an oven at a temperature of 90 ° C for 3 hours.

To solve the problem of achieving the required bends of the film elements, so that the cylindrical surfaces of the shells are located relative to each other at an angle of 90 °, the directional folding method is used to separate the film elements from the substrate. In particular, for example, a method based on directional etching of the sacrificial layer due to different sizes of internal mechanical stresses at the borders of the window or the edges of the film element, which leads to stimulation of etching from the boundaries at which there is a maximum of elastic stresses (see Figure 6). In the structure of the film element among the forming layers of GaAs and InGaAs, the latter is stressed (see Fig. 3, a)). The contours of the forming layers are drawn so that the maximum values of the built-in mechanical stresses are at those edges of the film element from which it is desirable to initiate the process of separating it from the substrate and which are perpendicular to each other. This condition is achieved due to the presence at the indicated edges of the stressed InGaAs layer 9 (see Fig. 6, right edge). Etching of the sacrificial layer 10 begins simultaneously from all sides, however, it proceeds at different speeds. On the right side of the film element, from the right edge (see Fig. 6) of GaAs / InGaAs, the released region of the film element is rolled into a cylindrical shell as the sacrificial layer is removed from under it 10. Here, the etching rate of the sacrificial layer is several orders of magnitude higher in compared with the rest of the edges of the film element, since the bending of the film element due to elastic stresses stimulates the access of the etchant to the sacrificial layer 10 and the removal of reaction products. At the other edges of the film element, the stressed layer 9 is absent, which leads to the absence of mechanical elastic stresses that bend the film element and thereby provide the etchant access to the sacrificial layer 10. As a result, there is a slow lateral etching of the sacrificial layer 10 in a narrow channel.

Example 5

On a GaAs semi-insulating substrate with a (100) orientation, multilayer film elements are formed that form pairs for sensor nodes intended for triaxial / biaxial measurements in two shells; from these pairs, an array is formed on the substrate with n = 2 precision identical elements with a given distribution in space, where n is the number of precision identical elements, taking into account the geometric configuration of each element and its spatial orientation. Materials, geometry, and internal mechanical stresses are selected to provide orientation of the cross-shaped Hall elements of the array of sensor nodes with Hall contacts in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector. At the stage of forming pairs of film elements, layers are formed that are forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts and current leads, layers of contact pads. Preliminarily, a pseudomorphic AlAs sacrificial layer 10 nm thick is formed on the substrate. In the manufacture of multilayer film elements, a shape-forming, mechanically stressed (compressed) layer of InGaAs is grown, and the second shape-forming layer is made in the form of a system of GaAs and AlGaAs layers, which simultaneously plays the role of a functional layer that is sensitive to a magnetic field with Hall contacts and current leads. A 13-nm-thick GaAs quantum well is formed in the layer system with an electron gas with an electron concentration of about 10 ¹¹ cm ^-2 . A quantum well is located between the layers of AlGaAs solid solution doped with SL. Moreover, the layers in the AlGaAs sequence a layer corresponding to a barrier, a GaAs layer corresponding to a quantum well, an AlGaAs layer corresponding to a barrier are arranged between a GaAs layer, which is a protective layer, and a forming layer located on a sacrificial layer grown on a substrate and made of InGaAs . The thickness of each multilayer film element is set equal to 100 nm. Forming and functional layers are formed by molecular beam epitaxy, observing the conditions of pseudomorphic growth, from these materials as having different lattice constants and capable of generating a transverse (Hall) voltage when an electric current flows in the plane of the layers and there is an external magnetic field perpendicular to their plane, due to the usual Hall effect (RSPopovic "Hall Effect Devices", IOP Publishing (2004)). The layer of contact pads, providing ohmic contact to the functional layer, is formed by sequential deposition of germanium (Ge), nickel (Ni) and gold (Au), followed by annealing. Drawings of layers, including drawings defining the contours of the film element, drawings of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from the latter to contact pads, contact pads are set using planar technology - lithographically.

The direction of bending of each multilayer film element during subsequent separation from the substrate is set during its formation by setting patterns of layers, including a pattern defining the contours of the film element, patterns of forming, mechanically strained, and functional, susceptible to magnetic fields, layers with Hall contacts with current leads from the latter to pads, drawings of pads. First, drawings are formed that define the contours of each film element — the contours of the formative and functional layers in the form of through windows in the layers to the sacrificial layer. For etching windows, an orthophosphoric acid based etchant (H ₃ PO ₄ : H ₂ O ₂ : H ₂ O / 3: 1: 50) is used. Then, the final part of the pattern formation is carried out, defining the cross-shaped Hall element of the sensor assembly, making the areas of current leads and contact pads, using the same etching agent for etching windows. During the formation of each multilayer film element, a drawing of a functional layer that is susceptible to a magnetic field, corresponding to two sensor nodes with Hall contacts, with current leads from the latter to the contact pads, is formed with a channel for transmitting current common to the two sensor nodes, lying in the direction of the film element bending, with a channel length of at least πR / 2, R is the radius of curvature of the shell. At the same time, two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage — potential contacts. Contacts are placed along the channel on opposite sides of it. The azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs is πR / 2, R is the radius of curvature of the shell. Each pair is designed to determine its orthogonal component of the external magnetic field. A drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with current leads from the latter to the contact pads, and the drawing of the contact pads themselves are formed lithographically by defining the shape of the cross-shaped Hall element, current leads and contact pads. The geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads. From current and potential contacts of Hall bridges by lithography and subsequent deposition of Au, conductors are laid to the contact pads located on the substrate, with ohmic contacts to the functional layer. Lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. To obtain ohmic contacts, germanium, nickel and gold are sequentially sprayed on the area of the contact areas specified by the figure, and annealed in a hydrogen atmosphere at a temperature of 450 ° C for 5 minutes. When two multilayer film elements are formed in pairs for sensor assemblies intended for triaxial / biaxial measurements consisting of two shells, their patterns are realized with the possibility of perpendicular directions of bending and obtaining shells of a cylindrical shape, the forming of which are perpendicular. For this, the layer patterns of the first film element are repeated in the second film element with a rotation of 90 °. Two pairs of film elements are formed, in each pair the pattern of the first film element is repeated in the second film element with a rotation of 90 °. Thus, the first film element of the first pair and the first film element of the second pair are precision identical, the second film element of the first pair and the second film element of the second pair are precisely the same.

Then, both film elements in each pair are separated from the substrate, transforming them under the action of internal mechanical stresses into shells with the orientation of the pairs of Hall contacts in space being achieved, in which the measured Hall stresses correspond to the three orthogonal components of the external magnetic field vector. To separate in each pair of both film elements from the substrate, the material of the element located under the film elements is removed — the material of the AlAs sacrificial layer, providing directional bending of each film element with the formation of a cylindrical shell. The required direction of bending of each film element of each pair is achieved by directional etching — selective lateral (lateral) etching of the sacrificial layer in the direction due to the anisotropy of the mechanical properties of the film element and its lithographic pattern. Poison the sacrificial layer in the etchant based on hydrofluoric acid (HF: H ₂ O / 1: 10). The etching of the sacrificial layer is carried out before the separation of each film element within the area on which the sensor nodes are located (see Figure 3). Thus, parts of the initially two flat film elements in pairs are transformed into cylindrical shells, while contact pads 1-6 with ohmic contacts are placed on the substrate, leaving them rigidly connected to the substrate due to the timely termination of lateral etching of the sacrificial layer. As a result of the transformation of each film element in pairs into a cylindrical-shaped shell, a channel for transmitting current is placed along the guide of the cylindrical shell, Hall contacts for measuring Hall voltage are placed along the channel on its opposite sides, and they withstand an azimuthal angle between pairs of Hall contacts of 90 °. In this case, the contact pads with ohmic contacts are placed on the substrate and are rigidly connected with it. Thus, an array of n sensor assemblies intended for three-axis / two-axis measurements consisting of two shells, with n = 2, made exactly the same with a given distribution in space, is obtained. In the final, the array is placed in a solid matrix of non-magnetic material, for this purpose a liquid polymer is applied to the substrate with the shells of the array and cured (see Figure 4). Before sealing the shells into the polymer, the formed structure is placed in ethyl acetate, which is a solvent of polydimethylsiloxane, and then transferred to unpolymerized polydimethylsiloxane. Substitution of ethyl ether inside the shells is carried out, as well as coating the surface of the shells from the outside. To polymerize polydimethylsiloxane and seal the structure into a polymer, it is heated in an oven at a temperature of 90 ° C for 3 hours.

The considered example of the method implementation relates to the manufacture of a sensor for triaxial / biaxial measurements of the magnetic field gradient.

Claims (24)

1. A magnetic field sensor containing sensor nodes implemented using the Hall effect, characterized in that the sensor nodes are made up of a curvilinear shell with a system of layers, among which are susceptible to the magnetic field are functional and shape-forming, the latter is provided with a curvature of the shell and the possibility of orientating crosswise Hall elements of sensor nodes in space with the compliance of the measured Hall stresses with the orthogonal components of the external magnetic field vector. 2. The sensor according to claim 1, characterized in that the sensor nodes are made for triaxial / biaxial measurements in two shells made of cylindrical shape and located relative to each other so that their generators are perpendicular to each other, each shell is equipped with sensor nodes with cross-shaped Hall elements including pairs of Hall contacts oriented in space with matching the measured Hall stresses to the three orthogonal components of the external magnetic field vector due to there is an azimuthal angle between the pairs of Hall contacts of each of these shells, equal to 90 °, or the sensor nodes are made for biaxial measurements in a single shell made of a cylindrical shape with pairs of Hall contacts of cross-shaped Hall elements of sensor nodes oriented in space with matching the measured Hall stresses two orthogonal components of the external magnetic field vector due to the azimuth angle between the pairs of Hall contacts, equal to 90 °. 3. The sensor according to claim 2, characterized in that the sensor nodes are made for triaxial / biaxial measurements in two shells made of cylindrical shape and arranged relative to each other so that their generators are perpendicular to each other, each shell is equipped with sensor nodes with cross-shaped Hall elements including pairs of Hall contacts oriented in space with matching the measured Hall stresses to the three orthogonal components of the external magnetic field vector due to there is an azimuthal angle between the pairs of Hall contacts of each of these shells, equal to 90 °, or the sensor nodes are made for biaxial measurements in a single shell made of a cylindrical shape with pairs of Hall contacts of cross-shaped Hall elements of sensor nodes oriented in space with matching the measured Hall stresses two orthogonal components of the external magnetic field vector due to the azimuth angle between the pairs of Hall contacts, equal to 90 °, and of these sensor nodes in two shells for triaxial / biaxial measurements or sensor nodes in one shell for biaxial measurements, an array is formed in which n≥2 sensor nodes are made exactly the same, with a given distribution in space. 4. The sensor according to claim 1, characterized in that the shell is located on the GaAs substrate, connected with it due to the AlAs sacrificial layer made on the substrate. 5. The sensor according to claim 1, characterized in that the forming layers are made of pseudomorphic monocrystalline from materials characterized in the free state by different periods of the crystal lattice, for layers located on the outside of the shell, materials with a large period of the crystal lattice are used. 6. The sensor according to claim 1 or 5, characterized in that the forming layers are made using GaAs and InGaAs materials. 7. The sensor according to claim 1, characterized in that in the system of layers, among which are susceptible to a magnetic field - functional and forming, the forming layer is made susceptible to a magnetic field. 8. The sensor according to claim 1 or 7, characterized in that in the system of layers susceptible to the magnetic field - functional and shape-forming, the layer susceptible to the magnetic field is made of GaAs or FePt. 9. The sensor according to claim 1, characterized in that the wall thickness of the shell is from about (5 ÷ 6) × 10 ^-10 to about 10 ^-5 m 10. The sensor according to claim 1, characterized in that in the system of layers susceptible to the magnetic field - functional and forming, a quantum well is made in the form of a 13 nm thick GaAs layer with an electron gas with a concentration of about 10 ¹¹ cm ^-2 , the quantum well is located between layers of AlGaAs solid solution doped with Si, the layers in the AlGaAs sequence being a barrier, GaAs as a quantum well, AlGaAs as a barrier located in the shell between the GaAs layer made from the side of the inner volume of the shell, which is a protective layer, and the forming layer located on the outside of the shell and made of InGaAs. 11. The sensor according to any one of claims 1 to 3, characterized in that two sensor assemblies are made in the cylindrical shell wall, mesostructures are lithographically formed with the formation of cross-shaped Hall elements - Hall bridges, a channel for transmitting current to the cross-shaped Hall sensor element node - the channel of the Hall bridge is located along the guide of the cylindrical shell, while in the sensor nodes along the channel there are two pairs of Hall contacts for measuring the Hall voltages are potential contacts, in each pair the contacts are located on opposite sides of the channel, the azimuthal angle between the pairs of contacts is 90 °, the channel common for two sensor nodes is made connecting current contacts common to two sensor nodes, length πR / 2 and more, R is the radius of curvature shells; in the case of a sensor operating on the basis of the ordinary Hall effect, the functional layer that is susceptible to the magnetic field, as well as the forming layer, is made of a cylindrical shape, in it the geometry of the cross-shaped Hall element - the Hall bridge is determined by the execution of current leads from current and potential contacts of the Hall bridges by lithography and subsequent deposition of Au are laid current leads to the contact pads located on the substrate, with ohmic contacts to the functional layer, ohmic contacts made by spraying a layer of germanium / nickel / gold, followed by annealing; in the case of a sensor operating on the basis of an extraordinary Hall effect, a functional layer that is susceptible to a magnetic field is made, in contrast to the forming layer, having a pattern in the form of two connected cross-shaped elements, which determines the geometry of the Hall bridge, the functional layer is obtained by preliminary applying a protective resist to the forming layer and forming in the resist a through window with a pattern in the form of two connected cross-shaped elements, followed by spraying FePt and phi into the window After deposition, removal of the protective resist, which has curvature, like the forming layer, in this case, the ohmic contacts to the functional layer are made directly at the protrusions of the Hall element - the Hall bridge, either on the contact pads, or between them at any point of the current leads, the latter are made also by lithography and subsequent deposition of Au and laid to the contact pads located on the substrate and made of gold, too, to obtain an ohmic contact, FePt and Au layers were made lap, and if the ohmic contacts are made at the protrusions of the Hall bridge, then the place where the layers are overlapped is located at the protrusions, if the ohmic contacts are made at the contact pads, the current guide regions are covered with FePt, and the FePt and Au layers are made at the contact pads overlap. 12. The sensor according to claim 1, characterized in that it is additionally equipped with signal processing circuits formed on the same substrate, on which the shell with sensor nodes is located. 13. The sensor according to claim 1, characterized in that the sensor nodes are made as part of a curved shell, which is sealed in a solid matrix of non-magnetic material. 14. A method of manufacturing a magnetic field sensor, characterized in that a multilayer film element / elements is formed on the substrate using materials, geometry and internal mechanical stresses that ensure the orientation of the cross-shaped Hall elements of the sensor nodes in space, in which the measured Hall stresses correspond to the orthogonal components of the vector external magnetic field, while at the stage of formation of the film element make layers, forming, mechanically strained and functional, susceptible to a magnetic field, with Hall contacts, the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into the shell with the achievement of the orientation of the cross-shaped Hall elements in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic vector fields. 15. The manufacturing method according to 14, characterized in that when forming a multilayer film element, all its structural layers are made in sequence from the substrate - forming, mechanically stressed, functional, susceptible to a magnetic field, with Hall contacts and current leads, layers of contact pads, in this case, by means of planar technology, patterns of layers are set, including patterns defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to the magnetic field, layers with Hall contacts, with conductors from the latter to the contact pads, contact pads. 16. The manufacturing method according to 14, characterized in that before the formation of the multilayer film element, a sacrificial layer located on a substrate is grown, the film element is separated from the substrate by selective side etching of the sacrificial layer, and a GaAs substrate is used as the substrate. 17. The manufacturing method according to any one of paragraphs.14-16, characterized in that the thickness of the multilayer film element is set from 5 × 10 ^-10 to 10 ^-5 m, while the patterns of the layers are formed lithographically, the subsequent separation of the film element from the substrate is carried out by removing material of the element located under the film element, thereby providing directional bending of the film element with the formation of a cylindrical shell of radius R with sensor nodes with cross-shaped Hall elements - Hall bridge, about oriented in space with realizing the correspondence of the measured Hall stresses to the orthogonal components of the external magnetic field vector, while the channel of the sensor node for passing the current of the Hall bridge is placed along the guiding cylindrical surface of the shell, pairs of Hall contacts for measuring Hall voltage are made in the sensor nodes — potential contacts, contacts are along the channel on its opposite sides, the azimuthal angle between the pairs of contacts of the Hall contacts is 90 °. 18. The manufacturing method according to 14, characterized in that the film element is separated from the substrate, transforming it under the influence of internal mechanical stresses into a shell containing two sensor nodes, with the achievement of the orientation of the cross-shaped Hall elements of the sensor nodes in the space, in which the measured Hall stresses to the orthogonal components of the external magnetic field vector, through the implementation of directional etching that performs a given direction of bending is released about the film element, and the direction of bending is set during the formation of the multilayer film element, when defining the layer patterns, including the pattern defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts and current leads from the latter to the contact pads, contact pads, moreover, a drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with conductors from the latter to the contact areas the dams are formed with a channel for transmitting current common to two sensor nodes, lying in the direction of bending of the film element, with a channel length of at least πR / 2, R is the radius of curvature of the shell, and two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage - potential contacts, contacts are located along the channel on different sides of it, the azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs πR / 2, R is the radius of curvature of the shell, each pair is designed to determine its the togonal component of the external magnetic field, the film element is transformed into a cylindrical shell, in the final the shell is placed in a solid matrix of non-magnetic material, for this purpose a liquid polymer is applied to the substrate and cured, when forming two multilayer film elements, their patterns are realized with the possibility repeating perpendicular directions of bending and obtaining shells of cylindrical shape, the generators of which are perpendicular, repeating the drawings of the layers of the first film element They are pressed in the second film element with a rotation of 90 °, in the final of the shell they are placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shells and cured. 19. The manufacturing method according to p. 15, characterized in that the film element is separated from the substrate, transforming it under the action of internal mechanical stresses into a shell containing two sensor nodes, with the achievement of the orientation of the cross-shaped Hall elements of the sensor nodes in the space at which the measured Hall stresses to the orthogonal components of the external magnetic field vector, through the implementation of directional etching that performs a given direction of bending is released about the film element, and the direction of bending is set during the formation of the multilayer film element, when defining the layer patterns, including the pattern defining the contours of the film element, patterns of forming, mechanically stressed, and functional, susceptible to magnetic fields, layers with Hall contacts and current leads from the latter to the contact pads, contact pads, moreover, a drawing of a functional layer susceptible to a magnetic field, with Hall contacts, with conductors from the latter to the contact areas the dams are formed with a channel for transmitting current common to two sensor nodes, lying in the direction of bending of the film element, with a channel length of at least πR / 2, R is the radius of curvature of the shell, and two pairs of Hall contacts are made in the sensor nodes for measuring Hall voltage - potential contacts, contacts are located along the channel on different sides of it, the azimuthal angle between the pairs of contacts is 90 ° or the center distance between the pairs πR / 2, R is the radius of curvature of the shell, each pair is designed to determine its the togonal component of the external magnetic field, the film element is transformed into a cylindrical shell, in the final the shell is placed in a solid matrix of non-magnetic material, for this purpose a liquid polymer is applied to the substrate and cured, when forming two multilayer film elements, their patterns are realized with the possibility repeating perpendicular directions of bending and obtaining shells of cylindrical shape, the generators of which are perpendicular, repeating the drawings of the layers of the first film element They are pressed in the second film element with a rotation of 90 °, in the final of the shell they are placed in a solid matrix of non-magnetic material, for this a liquid polymer is applied to the substrate with the shells and cured. 20. The manufacturing method according to 14, characterized in that the forming, mechanically stressed layers are formed by epitaxy from crystalline materials with different lattice constants, observing the conditions of pseudomorphic growth, a functional, magnetic field susceptible layer is performed by epitaxy from a semiconductor or sprayed from metal . 21. The manufacturing method according to claim 20, characterized in that the forming mechanically stressed layers are formed by epitaxy from crystalline materials with different lattice constants — GaAs and InGaAs, and the functional, magnetic-susceptible layer is made of GaAs or FePt. 22. The method according to claim 20, characterized in that the functional layer that is susceptible to magnetic field is made in the form of a system of layers, among which a 13 nm-thick GaAs quantum well with an electron gas with a concentration of about 10 ¹¹ cm ^{-2 is made} , a quantum well is arranged between the layers of AlGaAs solid solution, in relation to which δ-doping of Si was carried out, the layers in the AlGaAs sequence, a layer corresponding to a barrier, a GaAs layer corresponding to a quantum well, an AlGaAs layer corresponding to a barrier, are placed between a GaAs layer, which is a protective layer and a forming layer located on a substrate or a sacrificial layer grown on a substrate and made of InGaAs. 23. The method according to p. 18 or 19, characterized in that the pattern of the functional layer that is susceptible to a magnetic field, with Hall contacts, with conductors from the latter to the contact pads in the case of manufacturing a sensor operating on the basis of the ordinary Hall effect, is formed with an external circuit , the same as in the forming layer, and the geometry of the cross-shaped Hall element - the Hall bridge is determined by the implementation of current leads, from the current and potential contacts of the Hall bridges by lithography and the subsequent application of Au gasket vayut tokovody to contact pads disposed on the substrate, with ohmic contacts to the functional layer, ohmic contacts is performed by spraying the layer of germanium / nickel / gold, followed by annealing; in the case of manufacturing a sensor operating on the basis of an extraordinary Hall effect, a functional layer that is susceptible to a magnetic field is made with a pattern different from the forming layer having a pattern in the form of two connected cross-shaped elements, which determines the geometry of the Hall bridge, the functional layer is obtained by preliminary applying a protective resist on the forming layer and forming in the resist a through window with a pattern in the form of two connected cross-shaped elements with subsequent spraying we put in the FePt window and the final, after sputtering, removal of the protective resist, in this case, ohmic contacts to the functional layer are made directly at the protrusions of the Hall element - the Hall bridge, either on the contact pads, or between them - at any point of the current leads, the conductors are also made by lithography and subsequent deposition of Au and laid to the contact pads located on the substrate and made of gold, to obtain an ohmic contact, the FePt and Au layers are overlapped, and if the ohmic The contacts are made at the protrusions of the Hall bridge, the place where the layers are overlapped is located at the protrusions, if ohmic contacts are performed on the contact pads, the current guide regions are covered with FePt, and in the area of the contact pads, the FePt and Au layers are lapped, while lithographic windows that define the geometry of current leads and pads are made with a depth sufficient for electrical insulation. 24. The method according to 14, characterized in that a multilayer film element (s) are formed on the substrate, respectively, for sensor assemblies intended for biaxial measurements as part of a single shell, or sensor assemblies intended for triaxial / biaxial measurements in two shells , from the specified element / elements form an array with n≥2 precision identical elements, taking into account their geometry and spatial orientation, with a given distribution in space, using materials, geometry and internal mechanical stresses ensuring orientation of the cross-shaped Hall elements of the array of sensor nodes for biaxial measurements or for triaxial / biaxial measurements in space at which the correspondence of the measured Hall stresses to the orthogonal components of the external magnetic field vector is realized, while layers are made at the stage of formation of each film element of the array, shape-forming, mechanically stressed, and functional, susceptible to a magnetic field, with Hall contacts, each film element of the array is separated from the substrate, transforming it under the action of internal mechanical stresses into the shell with the achievement of the orientation of the cross-shaped Hall elements in space, in which the measured Hall stresses correspond to the orthogonal components of the external magnetic field vector, with the receipt of an array of sensor nodes for biaxial measurements in the composition one shell, made exactly the same, with a given distribution in space, with n≥2 exactly the same sensor nodes E, or to obtain an array of sensor units intended for triaxial / biaxial measurement of two shells and made precisely equal, in a predetermined distribution in space, with n≥2 precisely the same sensor nodes.

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