BG67425B1 - Integrated hall effect sensor - Google Patents

Abstract

The integrated Hall effect sensor contains four identical semiconductor wafers with n-type hopping conduction and a rectangular shape - first (1), second (2), third (3) and fourth (4). On one of the sides of each wafer (1, 2, 3 and 4) are formed successively at equal distances from left to right three rectangular ohmic contacts - first (5, 6, 7 and 8), second (9, 10, 11 and 12) and third (13, 14, 15 and 16), as the first (5, 6, 7 and 8) and the third contacts (13, 14, 15 and 16) are terminal and the second contacts (9, 10, 11 and 12) are central. The wafers (1, 2, 3 and 4) lie in one plane, as the contacts (6, 7, 8, 10, 11, 12, 14, 15 and 16) are parallel to both their long sides and the long sides of the the contacts (5, 9 and 13) of the first wafer (1). All contacts (5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16) are located either only on the upper or only on the lower surface of the wafers (1, 2, 3 and 4). The contacts (9 and 11) of the first (1) and third (3) wafer are connected to a current source (17). The contact (5) of the wafer(1) is connected to the contact (14) of the second wafer (2), the contact (13) of the wafer (1) is connected to the contact (8) of the fourth wafer (4), the contact (6) of the wafer (2) is connected to the contact (15) of the third wafer (3), and the contact (7) of the wafer (3) is connected to the contact (16) of the fourth wafer (4). The differential output (18) of the sensor are the contacts (10 and 12), as the measured magnetic field is parallel to the plane of the wafers (1, 2, 3 and 4) and to the long sides of the contacts (5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16).

Description

Field of technology

The invention relates to an integrated Hall sensor applicable in the field of robotics, including robotic, minimally invasive surgery and telemedicine; quantum communication; sensors; security systems with artificial intelligence; non-contact measurement of linear and angular displacements; low-field magnetometry; electric cars and hybrid vehicles; contactless automation; navigation; multi-rotor unmanned systems, space research and military; counter-terrorism, including underwater, ground and air surveillance and prevention, etc.

BACKGROUND OF THE INVENTION

An integrated Hall sensor is known, containing a semiconductor substrate with a rectangular shape and n-type impurity conductivity, on one side of which are formed at equal distances three rectangular ohmic contacts parallel to their long sides - one central and two end. The end contacts are symmetrical to the central one. With one load resistor the end contacts are connected to one terminal of the current source, the other terminal of which is connected to the central contact. The differential output of the Hall sensor is the end contacts, as the measured magnetic field is parallel to the plane of the substrate and the long sides of the contacts, [1-12].

The disadvantage of this integrated Hall sensor with plane sensitivity is the presence of parasitic output voltage in the absence of magnetic field (offset) due to geometric and electrical asymmetry arising from misalignment in the location of the end contacts relative to the central, unavoidable technological imperfections, mechanical stresses chip enclosure, temperature changes, etc.

Another disadvantage is the complicated implementation through the integrated silicon technologies used in microelectronics, which requires different in nature physicochemical processes in the construction of the silicon substrate with planar contacts and in the formation of load resistors.

Technical essence of the invention

The object of the invention is to create an integrated Hall sensor with reduced offset and simplified technological implementation.

This problem is solved with an integrated Hall sensor containing four identical semiconductor substrates with n-type impurity conductivity and rectangular shape - first, second, third and fourth. On one of the sides of each pad are formed from left to right in series and at equal distances by three rectangular ohmic contacts - first, second and third, the first and third are end and the second are central. The pads lie in one plane, the contacts are parallel to their long sides and are located either on the upper or only on the lower surface of the pads. The central contacts of the first and third pads are connected to a power source. The first contact of the first pad is connected to the third contact of the second, the third contact of the first pad is connected to the first contact of the fourth, the first contact of the second pad is connected to the third contact of the third, and the first contact of the third pad is connected to the third pin. on the fourth. The differential output of the Hall sensor is the central contacts of the second and fourth pads, the measured magnetic field being parallel to the plane of the pads and the long sides of the pins.

An advantage of the invention is the strongly reduced parasitic output voltage (offset) of the sensor, due to the original connection of the end contacts of the four identical substrates, leading to shortening of the inevitable parasitic potentials in the structures by compensating currents. field, including in the areas of the two output contacts.

Another advantage is the full technological compatibility through the same type of physicochemical processes of silicon integrated technologies used in microelectronics for the realization of all four structural components of the Hall sensor.

Another advantage is the high conversion efficiency (sensitivity) as a result of generating in a magnetic field additional Hall potentials with different polarity (sign) respectively on the second and fourth substrate through their end contacts connecting them to the first and third substrate, which leads to amplification of the Hall output voltage.

Another advantage is the increased measurement accuracy of the integrated Hall sensor, due to the significantly minimized parasitic offset and high magnetic sensitivity.

Explanation of the attached figure

The invention is illustrated in more detail by one embodiment thereof, given in the attached figure 1.

Examples of the invention

The integrated Hall sensor contains four identical semiconductor substrates with n-type impurity conductivity and rectangular shape - first 1, second 2, third 3 and fourth 4. On one of the sides of each substrate 1, 2, 3 and 4 are formed from left to right successively and at equal distances on three rectangular ohmic contacts - first 5, 6, 7 and 8, second 9, 10, 11 and 12, and third 13, 14, 15 and 16, as the first 5, 6, 7 and 8 and third 13 , 14, 15 and 16 are finite and the second 9, 10, 11 and 12 are central. Pads 1, 2, 3 and 4 lie in one plane, contacts 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16 are parallel to their long sides and are located or only on the upper, or only the lower surface of the pads 1, 2, 3 and 4. The central contacts 9 and 11 of the first 1 and third 3 pads are connected to a current source 17. The first pin 5 of the first pad 1 is connected to the third pin 14 of the second 2, the third contact 13 of the first pad 1 is connected to the first pin 8 of the fourth 4, the first pin 6 of the second pad 2 is connected to the third pin 15 of the third pad 3, and the first pin 7 of the third pad 3 is connected to the third pin 16. 4. The differential output 18 of the Hall sensor is contacts 10 and 12 of the second 2 and fourth 4 pads, the measured magnetic field 19 being parallel to the plane of pads 1, 2, 3 and 4 and the long sides of pins 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16.

The operation of the integrated Hall sensor according to the invention is based on the generation of a Hall voltage with magnetic field B 19 applied parallel to the plane of the semiconductor structures 1, 2, 3 and 4 (contrary to the conventional activation of the Hall phenomenon perpendicular to The surface of semiconductors is field B. (19) This pattern was first discovered and used by Ch. Rumenin and P. Kostov, [1-8] and was further developed by S. Lozanova, [10-12]. the plane-magnetosensitive Hall effect, which builds on the variety of elements and structures in the microelectronic sensor, Figure 1. In this figure the four pads 1, 2, 3 and 4 are schematically located in four parallel planes, but in the microelectronic implementation of the sensor they are formed in one plane, that of the silicon chip.The action of the new solution is as follows: Given the planarity of the ohmic contacts 5, 6, 7, 8, 9, 11, 13, 14, 15 and 16, Figure 1, when and the source E s 17 and in the absence of a magnetic field 19, B = 0, they represent equipotential planes for the current lines. The current trajectories through these ten contact surfaces 5, 6, 7, 8, 9, 11, 13, 14, 15 and 16 are initially directed vertically downwards in the volume of pads 1, 2, 3 and 4, then become parallel to their upper surfaces, and finally again perpendicular to the planar ohmic contacts 5, 6, 7, 8, 9, 11, 13, 14, 15 and 16. Therefore, the current lines in pads 1, 2, 3 and 4 are curvilinear. According to the innovative connection of the contact pairs 5-14, 6-15, 7-16 and 8-13, current components I17 / 2 with the same value flow through them (as a result of the symmetry and the same dimensions of the same type of pads 1, 2, 3 and 4), equal to half of the total supply current I17 = I9.11 through the central contacts 9 and 11. However, the directions of the two currents I17 / 2 = I ₉ , _11/2 are opposite. As a result of inevitable geometric asymmetry - misalignment of the masks in the location of the end contacts 5, 13, 6, 14, 7, 15, 8 and 16 relative to the central 9, 10, 11 and 12, inevitable technological imperfections and structural defects, mechanical stresses at chip housing and bus metallization, temperature fluctuations, etc., at the output Vis = V ₁₀ , 12, 18, the configuration of Figure 1 in the absence of magnetic field B 19, B = 0, offset V1s occurs (B = 0) ^ 0. In fact, the presence of such a parasitic output voltage V18 means that in the identical symmetrical structures 1, 2, 3 and 4 there is an electrical asymmetry. In the new solution the overcoming of this significant sensory defect (offset) is achieved by the direct connection of contacts 5-14, 6-15, 7-16 and 8-13 of the pads 1, 2, 3 and 4. In this non-standard shortening compensating (equalizing) currents between the pads 1, 2, 3 and 4, equalizing the electrical conditions (potentials) in them. Therefore, in the zones of the two output contacts 10 and 12, in the absence of magnetic field B 19, B = 0, the offset is drastically reduced or compensated (reset), V ₁₈ (B = 0) = V ₁₀ , ₁₂ (B = 0). ) ~ 0. This approach compared to the complex dynamic offset compensation through the so-called. current spinning is significantly simplified and is immanent to the technical solution itself, and the end results in both cases are very close.

Application of the measured magnetic field B 19 parallel to the plane of the pads 1, 2, 3 and 4 and on the long sides of contacts 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16 leads to lateral (lateral) deviation of nonlinear current lines along their entire length. This effect is due to the Lorentz forces F _L , i, Fl = qVdr x B, where q is the elementary load of the electron, and V * is the vector of the average drift velocity of the moving electrons in the volumes of the substrates 1, 2, 3 and 4, [6, 8, 10-12]. (In Figure 1, the magnetic vector B 19 is perpendicular to the cross sections of structures 1, 2, 3 and 4). As a result of the Lorentz deviation from the forces Fl, i, depending on the directions of the supply currents in the pads 1, 2, 3 and 4, and the magnetic field B 19, the nonlinear trajectories lengthen and / or shorten accordingly. For this reason, Hall potentials with the same sign are generated simultaneously on the planar contacts 5, 14, 6 and 15, as well as on the output terminal 10, for example + V _H5 (B), + V _h14 (B), + Vh ₆ B), + V _h15 (B) and + V _H10 (B). Hall contacts are also generated simultaneously on contacts 7, 16, 13 and 8, as well as on the other output terminal 12, but with opposite sign -V _H7 (B), -V _H16 (B), -V _H1 h (B), -V _H 8 (B) and -V _H12 (B). Therefore, a Hall voltage, V ₁₈ (B) = V ₁₀ , ₁₂ (B) occurs at the differential output 18 of the sensor. It is generated by the opposing supply currents I ₁₄ , ₆ and I ₈ , ₁₆ in the second 2 and fourth 4 pads. Thus the output voltage

V ₁₀ , ₁₂ (B) is the result of Hall potentials with opposite sign on contacts 10 and 12. The signal V ₁₈ (B) is a linear and odd function of the strength and direction of the total supply current I ₉ , ₁₁ and the magnetic field B 19 .

However, the new solution uses an innovative method to further increase the magnetosensitivity of the Vis (B) output using equal but opposite Hall Hall potentials generated by the currents flowing in the first 1 and third 3 pads. In essence, structures 1 and 3 together with contacts 5, 9 and 13, and 7, 11 and 15, respectively, are three-contact plane-sensitive Hall elements, [1-3,5,6,8-12]. Generated by these sensors in magnetic field B 19 Hall potentials by directly connecting contacts 5-14 and 6-15, both 7-16 and 8-13 simultaneously further raise and / or lower the overall potential state of the second 2 and fourth 4 pads with terminals 10 and 12 forming output 18 of the sensor. The connection method and the arrangement of the pads 1, 2, 3 and 4 applied in the configuration of Figure 1 perform the summation of the output 18 of all the voltages generated in the Hall structures. To ensure this result of increasing the Hall signal Vi8 (B) all contacts 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16 must be located on the same side of the pads 1, 2, 3 and 4, only on the upper or only on the lower surface. Thus, the Lorentz forces F _l , i acting on the moving current carriers (electrons) by connecting realize on the surfaces of substrates 2 and 4 with output contacts 10 and 12 additional potentials with the same sign as formed on these terminals by the flow of currents I ₁₄ , ₆ and I ₈ , ₁₆ . Otherwise (in other configurations of connection and arrangement of pads 1, 2, 3 and 4 with contacts) the additional potentials will reduce the output signal and will not increase it. As a result of the proposed connection method of Figure 1, the output voltage V18 (B) is significantly increased and the magnetosensitivity increases. At the same time, the ohmic resistances of the second 2 and fourth 4 pads perform the functions of load resistors connected to the terminal contacts 5 and 13 of the first 1, and 7 and 15 of the third 3 pads. Thus, there is no need to use complex technological operations and processes to implement the two load resistors of the known solution. Full technological compatibility is achieved through the same type of physicochemical processes of silicon technologies for the implementation of the new Hall sensor. The minimized parasitic offset and the increased conversion efficiency significantly increase the measurement accuracy of the system of Figure 1.

The unexpected positive effect of the new technical solution is that through the original design and the innovative connection of pads 1, 2, 3 and 4 an additional Hall voltage is achieved, which is in phase summed with the output signal, generating increased sensitivity. At the same time, one of the most serious shortcomings is drastically reduced - offset through equalizing currents, including and significantly simplifies the technological implementation.

The implementation of the Hall sensor is performed with CMOS or BiCMOS integrated processes in a single technological cycle on a silicon wafer (silicon chip). The configuration of the four n-type structures 1, 2, 3 and 4, Figure 1, is formed in the plane of the chip, observing the orientation and functionalities of the planar ohmic contacts 5, 6, 7, 8, 9, 10, 11, 12 , 13, 14, 15 and 16, according to the new decision. In this case, pads 1, 2, 3 and 4 are n-type "pockets" in p-Si plates. They are performed with ion implantation and are strongly doped n-n zones in n-Si "pockets". Integrated technologies allow the simultaneous formation of the same chip and the processing electronic circuitry for the output voltage V18 (B), depending on the specific application, including the implementation of digital sensor platforms. The configuration of Figure 1 is also workable in the field of low temperatures, for example, the boiling point of liquid nitrogen T = 77 K, which expands the scope of application for the purposes of cryotronics, especially in low-field magnetometry and counterterrorism.

Claims (1)

Integrated Hall sensor, containing a rectangular semiconductor substrate with n-type impurity conductivity, on one side of which three rectangular ohmic contacts are formed successively at equal distances from left to right - first, second and third, the first and third are terminal and the second - central, all parallel to its long sides, the measured magnetic field is parallel to the plane of the substrate and the long sides of the contacts, there is another power source, one terminal of which is connected to the central contact of the substrate, characterized by the fact that there are others three semiconductor pads - second (2), third (3) and fourth (4), identical to the first (1), on one of the sides of which also from left to right are formed successively at equal distances on three rectangular ohmic contacts - first (6) , 7 and 8), second (10, 11 and 12), and third (14, 15 and 16), with the first (6, 7 and 8) and third (14, 15 and 16) contacts being terminal and the second contacts (10, 11 and 12) - central, as sub the pins (1, 2, 3 and 4) lie in one plane, and the contacts (6, 7, 8, 10, 11, 12, 14, 15 and 16) are parallel to both their long sides and the long sides of the contacts (5, 9 and 13) of the first pad (1), all contacts (5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 and 16) being located either only on the upper or only on the lower surface of the substrates (1, 2, 3 and 4), the central contact (11) of the third substrate (3) is connected to the other terminal of the current source (17) and the first contact (5) of the first substrate (1) ) is connected to the third contact (14) of the second substrate (2), the third contact (13) of the first substrate (1) is connected to the first contact (8) of the fourth substrate (4), the first contact (6) of the second substrate (2) is connected to the third contact (15) of the third substrate (3), and the first contact (7) of the third substrate (3) is connected to the third contact (16) of the fourth substrate (4), as the differential output (18). ) of the Hall sensor are the contacts (10 and 12) of the second (2) and fourth (4) pads a