BG66624B1 - Two-dimensional magnetometer - Google Patents

Abstract

The two-dimensional magnetometer, contains a solid-state n-type pad on one side of which have formed two square ohm contacts (2) and (3), located close to one another. Symmetrically in relation to the four countries has consistently clockwise in a rectangular ohm contact-first (4) and (5), second (6) and (7), third (8) and (9), and fourth (10) and (11), all with the same dimensions. Each of the two groups, containing a square (2) and (3) and four rectangular socket (4) and (5), (6) and (7) and respectively (8) and (9), (10) and (11) is surrounded with deep p-type ring (12). Contacts (2) and (3) are joined with current supply (13). The first (4) and (5) and the second (6) and (7) contacts from each group, respectively, are related to each other. Fourth (10) and (11) and respectively third (8) and (9) contacts from each group are the exits (14) and (15) of the two-dimensional magnetometer for the two orthogonal components of the magnetic field (16), lying in the plane of the n-type pad (1).

Description

Technical field

The invention relates to a two-dimensional magnetometer applicable in the field of sensor micro- and nano-technologies, systems engineering, including bioengineering, robotics and mechatronics, contactless measurement of angular and linear displacements, biomedical research, energy and energy objects, automation positions , control technology and low-field magnetometry, military and security, and more.

BACKGROUND OF THE INVENTION

A two-dimensional magnetometer comprising a n-type semiconductor substrate is known, on one side of which a central ohmic contact with a square shape is formed, with a rectangular internal ohmic contact and an external ohmic contact alternately at its four sides. The four external contacts are connected and connected to the central contact via a power source. The measured external magnetic field lies in the plane of the n-type substrate, with each pair of opposite internal contacts relative to the central one being the outputs of the two-dimensional magnetometer for the two orthogonal plane components of the magnetic field vector [1,2].

The disadvantage of this two-dimensional magnetometer is the reduced accuracy of the individual sensor channels when measuring the plane components of the magnetic field as a result of the parasitic interchannel influence of the surface flow of the four supply currents between the central and four terminal contacts.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a two-dimensional magnetometer with high measurement accuracy of the two sensor channels.

This problem is solved by means of a two-dimensional magnetometer containing a n-type semiconductor substrate, on which one side is formed adjacent to each other by two square-shaped ohmic contacts, spaced and symmetrically with respect to the four sides of each of them. clockwise one rectangular ohmic contact - first, second, third and fourth, all of the same size. Each of the two groups containing square and four rectangular contacts is surrounded by a deep p-type ring. The two square contacts are connected to a power source. The first and second contacts of each group are linked. The fourth and third contacts of each group, respectively, are the outputs of the two-dimensional magnetometer for the two orthogonal components of the magnetic field lying in the plane of the n-substrate.

An advantage of the invention is the high measurement accuracy of the two sensor channels due to the greatly reduced surface flow of the supply current achieved by the p-ring surrounding the two contact groups.

An advantage is also the increased magnetosensitivity of the two sensor channels as a result of the sequential connection of the outputs of the two transducers formed by the two groups of ohmic contacts and the presence of the deep p-ring surrounding them.

An advantage is the increased signal-to-noise ratio and resolution of the measured magnetic induction from the increased sensitivity of the sensor channels.

Explanation of the attached figure

The invention is explained in more detail by an exemplary embodiment given in the annexed figure 1.

Examples of carrying out the invention

The two-dimensional magnetometer contains a n-type semiconductor support 1, on which one square-shaped ohmic contacts 2 and 3 are formed on one side of each other and are spaced symmetrically with respect to the four sides of each of them. arrow on one rectangular ohmic contact - first 4 and 5, second 6 and 7, third

66624 B1 and 9 and Quarters 10 and 11, all of the same size. Each of the two groups containing square 2 and 3 and four rectangular contacts 4 and 5, 6 and 7, respectively 8 and 9, 10 and 11 is surrounded by a deep p-type ring 12. The two square contacts 2 and 3 are connected by source 13. The first 4 and 5 and respectively the second 6 and 7 contacts of each group are interconnected. The fourth 10 and 11 and respectively the third 8 and 9 contacts of each group are the outputs 14 and 15 of the two-dimensional magnetometer for the two orthogonal components of the magnetic field 16 lying in the plane of the n-type substrate 1.

The action of the two-dimensional magnetometer according to the invention is as follows.

When the two square pins 2 and 3 are connected to the power source 13, a supply current 1 ₂₃ flows between them. Its trajectory in the areas under contacts 2 and 3 is initially perpendicular to the upper surface of the n-pad 1, since the square low-ohmic contacts 2 and 3 represent equipotential planes. The other part of the effective current path 1 _{2 3} is in the volume of the n-pad 1 and is parallel to its upper side. An important feature is that the directions of current 1 ₂₃ below the square contacts 2 and 3 are opposite, 1 ₂ = | -1 ₃ | = 1 _{2 3} . The deep p-type ring surrounding sufficiently close ohmic contacts 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 drastically reduces the drainage on the surface of the supply current substrate 1 _{23 23} .

The external magnetic field B 16, which is of arbitrary orientation in the plane of the substrate 1, through its two mutually perpendicular components _{χ χ} and B _y leads to the emergence of corresponding laterally deflecting current carriers 1 ₂₃ Lorentz forces, P _E = μ W _0r x B, where ς is the elemental load of the electron and Y _0r is the vector of the average drift velocity of the carriers, in our case electrons. As a result of this Lorentzian deflection, in the surface areas where ohmic contacts 4 and 8, and respectively 10 in one group and 5 and 9, and 7 and 11 in the other respectively, are generated, opposite electric signs are generated. This leads to the appearance of Hall stresses on these contacts as follows: Y ₄₈ (B _x ) and Y ₆₁₀ (B _y ), and respectively Y ₅₉ (B _x ) and Y _{7 and} (B _y ). Due to the structural symmetry of the two groups of contacts and the opposite direction of current 1 _{2 3} under contacts 2 and 3, these voltages are equal in value and have opposite polarity, Y _{4 8} (B _x ) = | - Y _{5 9} (B _x ) | and Y _6y (B _y ) = | - Y ₇ '(B) |. When the two first 4 and 5 and the two second 6 and 7 contacts of each group are connected respectively to each other, the Hall stresses are summed up: Y _{8 9} (Β _χ ) = Y _{4 8} (Β _χ ) + Y _{5 9} ( In _x ) and Y _6] , (B) = \ ₁₀ (Y _y ) + Y ₇₁ , (B). Therefore, twice the Hall voltages are generated on the differential outputs Y _{W | 1} (H _y ) 14 and Y ₈₉ (H _x ) 15 of the biaxial vector magnetometer than if only one magnet converter configured by one group of ohmic contacts is used , eg 2,4,6, 8 and 10. The two output Stroke signals 14 and 15 are linear and odd functions of the values and directions of the components Β _χ and B _y of field B 16, and therefore guarantee high metrological quality of 2-Ό sensor. The absolute value of the vector of the magnetic field B 16 in the x-y plane of the n-pad 1 and the angle Θ of the field B 16 with respect to a fixed reference axis in the same plane are given by the expressions: | B | = (B _x ² + Wu ² ) ^1/2 and Θ = 1ap - '(B (Wu) / B _x (B _x )).

The unexpected positive effect of the new technical solution lies in the possibility of generating two by two linear and odd Hall voltages registering the components of the plane magnetic vector B (B, B) with the same power supply 1 ₂ through two maximally simplified ohmic contacts configurations. . After summing the output signals without additional circuitry, the magnetic sensitivity of the two outputs 14 and 15 is practically doubled. It is essential to simplify the subsequent processing of output voltages 14 and 15 that the selected symmetrical structure determines the equality of the magnetic sensitivities of outputs 14 and 15. Surface parasitic currents are drastically minimized by the specific geometry of the p-type ring 12. Their flow to the surface has been virtually eliminated and the measurement accuracy of the two sensor channels has been significantly improved. The deep p-ring 12 also improves the orthogonality of currents 1 ₂ and 1 ₃ through the two square power contacts 2 and 3 in the absence of a magnetic field B 16 with respect to the upper plane of the substrate 1. Thus, the current lines 1 _{2 3} penetrate deeply into the volume of n- semiconductor pad 1. Therefore, the effect of the two components B and B on the magnetic field B 16 by

X at the Lorentz force P _b on currents 1 ₂ and 1 ₃ is significantly increased, and the magnetic sensitivity of both channels is also.

66624 B1

The experiments performed with prototypes of the new two-dimensional magnetometer, based on the silicon bipolar technology according to the invention and comparing the results with the known solution, show that at a fixed value of the supply current 1 _{2 3} = const! and a certain direction of the magnetic field B 16 in the plane of the η-δϊ substrate 1, the magnetic sensitivities of the two x- and y-sensor channels 14 and 15 are equal and twice as large. One of the most important sensory parameters of the x- and y-channels is also improved - the signal-to-noise ratio δ / Ν. It has been found that the parasitic influence between the two sensor channels is substantially minimized and the measurement accuracy of the two-dimensional magnetometer is significantly increased. If necessary, the 2-magnetometer can be implemented with micromachining silicon technology.

Claims (1)

Claims 1. A two-dimensional magnetometer comprising a semiconductor n-type substrate, on one side of which is formed an ohmic contact with a square shape and rectangular ohmic contacts symmetrically relative to it, a source having an external magnetic field lying in the plane of the semiconductor substrate, characterized in that that the square ohmic contacts are two (2 and 3) and are located close to each other, at distances and symmetrically to the four sides of each of them, clockwise one rectangular ohmic horse act - first (4 and 5), second (6 and 7), third (8 and 9) and fourth (10 and 11), all of the same size, each of the two groups containing the square (2 and 3) and the four rectangular contacts (4 and 5), (6 and 7) and respectively (8 and 9) (10 and 11) are surrounded by a deep p-type ring (12), with the two square contacts (2 and 3) connected by the source (13) and the first (4 and 5) and respectively the second (6 and 7) contacts of each group are interconnected, whereby the fourth (10 and 11) and respectively the third (8 and 9) contacts of each group are the outputs (14 and 15) of the two-dimensional magnetometer for the two orthogonal components and the magnetic field (16) lying in the plane of the n-type substrate (1).