BG66640B1 - Semiconductor three-component magnetometer - Google Patents

Abstract

The semiconductor three-component magnetometer contains a n-type semiconductor wafer (1) in a rectangular shape, as at its surface has two elongated ohmic contacts (3 and 4), which are connected through a direct current source (9). The magnetic field (10) is in any direction to the wafer (1), and the rectangular n-wafer (1) is surrounded by a deep p-ring (2). Along the long sides of the inner zone there are also four identical elongated ohmic contacts - first (5), second (6), third (7) and fourth (8), as the first (5) is located opposite the second (6), and the third (7) is opposite the fourth (8). All ohmic contacts (3, 4, 5, 6, 7 and 8) are symmetrical to the centre of enclosed by the p-ring (2) the inner zone. To measure the first orthogonal component of a magnetic field, the first (5) and fourth (8) and respectively the second (6) and third (7) contacts are connected to each other, as the second (6) and fourth (8) are the output ( 11) for the first orthogonal component. To measure the second orthogonal component, the first (5) and third (7), and respectively the second (6) and fourth (8) contacts are connected to each other, as the output (12) for the second component are the two points of connection. To measure the third orthogonal component of the magnetic field, the four ohmic contacts (5, 6, 7 and 8) are connected, as the contacts (3 and 4) are connected through a high-ohmic trimmer (13), the midpoint of which and the contact point of the contacts (5, 6, 7 and 8) are the output (14) for the third orthogonal component.

Description

(54) SEMICONDUCTOR THREE-COMPONENT MAGNETOMETER

Field of technology

The invention relates to a semiconductor three-component magnetometer applicable in the field of sensorics, systems engineering, robotics and mechatronics, micro- and nano-technologies, including bioengineering, non-contact measurement of angular and linear displacements, positioning of objects in space, non-contact automation , energy and energy efficiency, control and measurement technology and low-field magnetometry, military affairs and security, etc.

BACKGROUND OF THE INVENTION

A semiconductor three-component magnetometer is known, measuring successively the three mutually perpendicular components of the magnetic field vector, containing a rectangular p-type semiconductor substrate, on one side of which on its short sides are formed one elongated ohmic base contact - first and second. Near the first basic contact and symmetrically on it is located a p-type emitter. Along the lengths of the long sides of the rectangular p-substrate are formed two elongated p-type collectors of equal size - the first and second are on one side, and the third and fourth on the other. The two base contacts are connected through a first current source, the emitter is connected in a forward direction through a second current source relative to the second base contact. The magnetic field has an arbitrary direction with respect to the semiconductor n-type substrate. To measure the first orthogonal component of the magnetic field, the first and fourth, and respectively the second and third p-collectors are connected to each other as the two connection points are connected by one load resistor and through a third current source the collector pairs are connected in the opposite direction to the second. basic contact. The output for the first orthogonal component are the two connection points of the collectors. To measure the second orthogonal component of the magnetic field, the first and second, and respectively the third and fourth p-collectors are connected to each other as the two connection points are connected by one load resistor and through the third current source the pairs of collectors are connected in the opposite direction to the second basic contact. The output for the second orthogonal component are the two connection points of the collectors. To measure the third orthogonal component of the magnetic field vector, the first and third, and respectively the second and fourth p-collectors are connected to each other as the connection points are connected by one load resistor and through the third current source the collector pairs are connected in the opposite direction. the second base contact. The output for the third orthogonal component are the two connection points of the collectors / 1, 3 /.

The disadvantage of this semiconductor three-component magnetometer is the very complicated construction, which requires three separate current sources and load resistors.

Another disadvantage is the reduced signal-to-noise ratio and the resolution of the individual output channels when measuring the magnetic induction as a result of the increased intrinsic noise from the bipolar transistor action of this magnetometer.

Technical essence of the invention

It is an object of the invention to provide a semiconductor three-component magnetometer with a simplified construction, high resolution and signal-to-noise ratio.

This problem is solved with a semiconductor three-component magnetometer containing a n-type semiconductor substrate, on one side of which a deep rectangular p-ring is formed; on the surface of the inner zone enclosed by this ring and near its short sides there are two elongated ohmic contacts - first and second; along the long sides of the inner zone there are four more identical elongated ohmic contacts - first, second, third and fourth. The first is located opposite the second, and the third is opposite the fourth, as all ohmic contacts are symmetrical with respect to the center of the inner zone enclosed by the ring. The power contacts are connected via a DC power source. The magnetic field has an arbitrary direction in space relative to the semiconductor n-type substrate. To measure the first orthogonal component of a magnetic field

Descriptions of issued patents for inventions № 03.1 / 15.03.2018 the first and fourth, and respectively the second and third contacts located along the long sides of the inner zone are interconnected as the second and fourth contacts are the output for the first orthotonal component. To measure the second orthogonal component of the magnetic field, the first and third, and the second and fourth contacts, respectively, located along the long sides of the inner zone are connected to each other, the output for the second orthogonal component being the two contact pairs. To measure the third orthogonal component of the magnetic field vector, the four ohmic contacts located along the long sides of the inner zone are connected as, the first and second power contacts are connected via a high-resistance trimmer, the midpoint of which and the connection point of the four contacts are the output for the third orthogonal component.

An advantage of the invention is the simplified construction due to the failure of two of the three power supplies and the load resistors, and also the total number of contacts is reduced by one.

Another advantage is the increased signal-to-noise ratio and the resolution of the individual output channels when measuring the magnetic induction due to the absence of bipolar transistor action, replaced by the stable and unambiguous as a sensory mechanism of operation Hall effect for all three channels.

Another advantage is the reduced parasitic interchannel influence in the sequential measurement of the magnetic components as a result of the improved structural and electrical symmetry of the magnetometer.

Description of the attached figures

The invention is illustrated in more detail by an exemplary embodiment thereof, given in the accompanying figures:

Figure 1 represents its basic construction;

Figure 2 (a), (b) and (c) show the three consecutive connections of the four elongated contacts along the long sides of the inner rectangular n-type zone of the substrate for sequentially measuring the three orthogonal components of the magnetic field vector.

Examples of the invention

The semiconductor three-component magnetometer contains a n-type semiconductor pad 1, on one side of which a deep rectangular p-ring 2 is formed. On the surface of the inner zone enclosed by this ring 2 and near its short sides there are two elongated ohmic contacts - first 3 and a second 4, and along the long sides of the inner zone there are four more identical elongated ohmic contacts - first 5, second 6, third 7 and fourth 8, the first 5 is located opposite the second 6 and the third 7 is against the fourth 8, all ohmic contacts 3, 4, 5, 6, 7 and 8 being symmetrical about the center of the inner zone enclosed by the p-ring 2. The supply contacts 3 and 4 are connected via a DC source 9. The magnetic field 10 has an arbitrary direction in space relative to the semiconductor n-type substrate 1. To measure the first orthogonal component of the magnetic field, the first 5 and the fourth 8, and the second 6, respectively. and the third 7 contacts are interconnected, the second 6 and fourth 8 contacts being the output 11 for the first orthogonal component. To measure the second orthogonal component of the magnetic field, the first 5 and third 7, and the second 6 and fourth 8 contacts, respectively, are interconnected, the output 12 for the second orthogonal component being the two connection points of the contact pairs 5 and 7, and 6 respectively. and 8. To measure the third orthogonal component of the magnetic field vector, the four ohmic contacts 5, 6, 7 and 8 are connected, the first 3 and second 4 supply contacts being connected via a high-resistance trimmer 13, the midpoint of which and the point of connecting the four contacts 5, 6, 7 and 8 are the output 14 for the third orthogonal component.

The operation of the semiconductor three-component magnetometer according to the invention (Figure 1) is as follows. When the two contacts 3 and 4 are connected to the source 9, a constant supply current I ₃ = const flows between them, the effective trajectory of which is curvilinear. It starts and ends on the low-impedance planar contacts 3 and 4, as in the areas below them the trajectory is initially № 03.1 / 15.03.2018

Descriptions of patents for inventions perpendicular to the upper surface of the n-substrate 1. The low-resistance supply contacts 3 and 4 are equipotential planes to which in the absence of an external magnetic field B 10 the current lines 1 ₃ are always perpendicular. The effective current trajectory 1 ₃ in the rest of the volume of the n-substrate 1 is parallel to its upper side. An important feature is that the directions of current 1 ₃ under contacts 3 and 4 are opposite, I ₃ = | -11 = 1 _{3 4} . The deep p-ring 2, surrounding the ohmic contacts 3,4, 5, 6, 7 and 8 close enough, drastically reduces the current flow 1 ₃ on the surface of the substrate 1. Given the chosen structural symmetry of all ohmic contacts 3, 4, 5, 6 , 7 and 8 with respect to the center of the inner rectangular n-type zone (the point of intersection of the diagonals of this region), the trajectory of the supply current 1 ₃ is also symmetrical with respect to this center in the x-y plane (Figure 1).

The external magnetic field B 10, which has an arbitrary orientation in space relative to the substrate 1, through its three mutually perpendicular components Β _χ , B _y and Β _ζ leads to the emergence of three laterally deflecting moving electrons 1 ₃ Lorentz forces, F _L = qV _{| r} x B, where q is the elementary charge of the electron, and V _di is the vector of the average drift velocity of the carriers along the y-axis [3]. As a result of this Lorentz deflection in the plane, in the surface zones, where the contacts 5, 6, 7 and 8 are located, additional electrical loads are generated from the Hall effect (Figure 1). This leads to the appearance of corresponding Hall potentials on these contacts from the three mutually orthogonal components of the magnetic field vector B 10 Β _χ , B _y and Β _ζ as follows: V _{5 6} (Β _χ ) and | - V _7g (B _x ) |; V ₅₇ (B _y ) and | - V _6g (B) |, h ± V _{5 678} (B _z ). The sequential connection in a certain way of the Hall contacts 5, 6, 7 and 8 aims at selective extraction of metrological information for the three separate orthogonal components Β _χ , B _y and Β _ζ of the magnetic vector B 10.

In the field Β _χ the Lorentz force F _L = q \ ' _{dl y} x Β _χ affects the vertical components of the drift velocity v _{|| y} of the electrons (Figure 1). When the four identical contacts 5, 6, 7 and 8 are connected crosswise (figure 2 (a)), a connection is made of contacts whose potentials generated in the magnetic field Β _χ by the Hall effect have the same sign and are equal in value, V ₅ (Β _χ ) = | - V ₆₇ (B) |. In this case, the differential output V _{6 8} (B) 11 between contacts 6 and 8 gives metrological information about the orthotonic magnetic component Β _χ .

In the B field, the Lorentz force F _L = qv _drx x Β _χ affects the vertical components of the drift velocity v _drx of the electrons (Figure 1). The parallel connection of contacts 5 and 7, and respectively 6 and 8 connects the contacts whose potentials generated in the magnetic field B _y by the Hall effect have the same sign and are equal in value, V _{5 7} (B) = | - 7 _{6 g} (B) |, (Figure 2 (6)). The differential output V _5g (B _y ) 12 between contacts 5 and 8 gives metrological information about the orthogonal magnetic component B.

y

Magnetic field B _z affects the lateral drift velocity v _drx and the vertical velocity component v ^. (Figure 1). Thus the corresponding Lorentz force F _L moves the trajectory 1 _{3 4} in the middle region of the substrate 1 in the plane x-y or to its upper surface or to its volume (depending on the directions of current I and the magnetic field B _z ), i.e. the Lorentz force F _L “shrinks” or “lengthens” the effective current trajectory 1 ₃ in the x-y plane. The connection of all Hall contacts 5, 6, 7 and 8 summarizes equal potentials generated by the orthogonal magnetic component B _z (figure 2 (b)). Thus, on all contacts 5, 6, 7 and 8, depending on the direction of the field B _z , both linear and polar (odd) Hall potential ± V _{5 6 7 g} (B _z ) and quadratic and even from the magnetic field B _{z are} generated. magnetoresistive signal MR ~ B ² z. The full compensation of the parasitic, in this case, quadratic magnetoresistance (the quadratic voltage on these Hall contacts 5, 6, 7 and 8 of the magnetic induction осъщест 10) is carried out by connecting to power contacts 3 and 4 and the current source 9 a high-impedance trimmer 13. the supply of the magnetometer is in DC mode I34 = const, the square magnetoresistive voltage V3 4 (B) ~ B ² z on the supply contacts 3 and 4 is distributed at the midpoint of the divider (trimmer 13) according to the values of the resistances of the two parts of trimmer 13. Thus the potential on the midpoint of trimmer 13 coincides with the square potential V _{5 6 7} generated in field B _z on the directly connected contacts 5, 6, 7 and 8, on

Descriptions of issued patents for inventions № 03.1 / 15.03.2018 which also arise quadratic voltage from the effect of magnetoresistance (figure 2 (b)). Full compensation of this parasitic quadratic voltage is achieved by resetting the output 14 in the absence of a magnetic field B _z = 0. Then the output 14 remains the linear and polar Hall voltage V _{5 6 7 g} (B _z ) ~ B _z , carrier of information on the third orthogonal magnetic component B _z .

An important feature is that each of the three consecutive connection configurations of contacts 5, 6, 7 and 8 (figure 2) corresponding to a particular orthogonal magnetic component performs suppression of the output voltages from the other two components of the vector B 10. These signals are are in-phase additions in the corresponding differential output and are compensated there. The structural symmetry of the new 3-D magnetometer significantly minimizes the parasitic interchannel influence - one of the main problems of vector magnetometry. The absolute value of the vector of the magnetic field B 10 is given by the expression: | = (Β _χ ² + By ² + Bz ² ) ^1/2 [3].

The unexpected positive effect of the magnetometer lies in the possibility of only six ohmic contacts, the same supply current 1 ₃ (one current source 9) and three different ways of switching on the four contacts 5, 6, 7 and 8, implemented in series (Figure 2 ( (a), (b) and (c)) to extract information about the total magnetic vector B 10. Since the sensor mechanism for converting the magnetic field B 10 into an electric signal is the stable and unambiguous Hall effect, the signal-to-noise ratio and the resolutions of the new 3-D magnetometer are high. The deep p-ring 2 minimizes the surface current flow 1 ₃ and improves the orthogonality of currents 1 ₃ and I through the two supply contacts 3 and 4 to the upper plane of the pad 1 in the absence of the magnetic field B 10. Thus the current lines 1 ₃ penetrate deep into the volume of the η-semiconductor substrate 1 and the lateral Lorentz deflection forces act more effectively on them. Therefore, the effect of the components Β _χ and Β _ζ on the magnetic field B 10 by the Lorentz forces F _L on currents 1 ₃ and I is significantly increased, and the sensitivity of these channels as well.

The magnetometer can be implemented with standard CMOS technology or micromachining and can be integrated together with the signal processing peripheral electronics. The sequential realization of the three connection configurations of contacts 5, 6, 7 and 8 (figure 2 (a), (b) and (c)) is carried out by means of a multiplexer.

Claims (1)

Patent claims 1. A semiconductor three-component magnetometer comprising a n-type semiconductor substrate, the surface of which has two elongated ohmic contacts - first and second, which are supply and are connected via a direct current source, the magnetic field being in any direction in space relative to the substrate, characterized in that a deep rectangular p-type ring (2) is formed on one side of the n-type pad (1) and the two supply contacts (3 and 4) are located in its inner zone near the short sides, along the long sides of this inner zone there are four more identical elongated ohmic contacts - first (5), second (6), third (7) and fourth (8), the first (5) being located opposite the second (6) , and the third (7) is opposite the fourth (8), as all ohmic contacts (3, 4, 5, 6, 7 and 8) are symmetrical with respect to the center of the inner zone enclosed by the p-ring (2), whereby for measurement of the first orthogonal component of the magnetic field the first (5) and the fourth (8), and respectively, the second (6) and third (7) contacts are interconnected, the second (6) and fourth (8) contacts being the output (11) for the first orthogonal component, for measuring the second orthogonal component of the magnetic field the first (5) and the third (7), and respectively the second (6) and the fourth (8) contacts are interconnected, the output (12) for the second orthogonal component being the two connection points of the contact pairs (5 and 7), and respectively and 8), for measuring the third orthogonal component of the magnetic field vector, the four ohmic contacts (5, 6, 7 and 8) are connected, the first (3) and the second (4) supply contacts being connected via a high-resistance trimmer (13). ), the midpoint of which and the point of connection of the four contacts (5, 6, 7 and 8) are the output (14) for the third orthogonal component.