BG67038B1 - A plane magneto-sensitive microsystem of hall effect sensor - Google Patents

Abstract

The plane magneto-sensitive microsystem of Hall effect sensor includes semi-conductive wafers of n-type conduction - from left to right first (1), second (2) and third (3), arranged parallel to each other and a current source (4). On one side of each of the wafers consecutively and at distances from each other are formed three rectangular ohmic contacts - first (5, 6 and 7), second (8, 9 and 10), and third (11, 12 and 13), as the second contacts (8, 9 and 10) are the central, and the first (5, 6 and 7) and third (11, 12 and 13) are symmetrical to them. One of the terminals of the current source (4) is connected to the central contact (8) of the first wafer (1), and the other - to the midpoint of a low-resistivity trimmer (14), the end terminals of which are connected to the contact (12) and to the contact (7). The contact (6) is connected to the contact (11), and the contact (5) - to contact (13). The differential output (15) of the microsystem of Hall effect sensor are the second contacts (9 and 10) of the second (2) and third (3) wafers, such as, the measurable magnetic field (16) is parallel to the plains of the wafers (1, 2 and 3) so and to the long sides of the contacts (5, 6, 7, 8, 9, 10, 11, 12 and 13).

Description

Field of technology

The invention relates to a plane-magnetosensitive Hall microsystem applicable in the field of sensors, the characterization of semiconductor wafers for the purposes of microelectronics, micro- and nanotechnologies, robotics and mechatronics, unmanned aerial vehicles, electric vehicles and hybrid bio-vehicle systems. research and robotic surgery, energy and energy efficiency, non-contact measurement of angular and linear displacements, control and measurement equipment and low-field magnetometry, military affairs and security.

BACKGROUND OF THE INVENTION

A planar-magnetic Hall-sensitive microsystem is known, containing two identical semiconductor pads with p-type impurity conductivity - first and second, located parallel to each other and a current source. On one side of each of the pads, successively and at distances from each other, five rectangular ohmic contacts are formed from left to right - first, second, third, fourth and fifth. The third contacts are central as the first and fifth, and respectively the second and fourth are symmetrically located relative to them. The contact pads form a microsystem with two plane-magnetic five-pin Hall sensors. All first and fifth contacts are interconnected. The second contact of the first pad is connected to the fourth of the second, and the fourth contact of the first to the second contact of the second pad. The terminals of the current source are connected to the second and fourth contact of the first pad. The differential output of the Hall microsystem is the two central contacts and the measured magnetic field is parallel to both the planes of the pads and the long sides of the contacts [1-4].

The disadvantage of this plane-magnetic Hall microsystem is its reduced magnetosensitivity, since only half of the total current through the respective power contacts is used in the semiconductor pads of the two microsensors.

Another disadvantage is the complicated design of the microsensor, containing ten contacts and a total of six connections between them.

Technical essence of the invention

The objective of the invention is to create a plane-magnetosensitive Hall microsystem with high magnetosensitivity and simplified construction - a smaller number of contacts and connections between them.

This problem is solved with a planar-magnetosensitive Hall microsystem, containing three semiconductor pads with p-type impurity conductivity - from left to right, first, second and third, located parallel to each other and a current source. On one side of each of the pads successively and at distances from each other are formed from left to right three rectangular ohmic contacts - first, second and third, the second contacts are central, and the first and third are respectively symmetrical to them. One terminal of the current source is connected to the central contact of the first pad, and the other to the midpoint of a low-resistance trimmer, the terminals of which are connected to the third contact of the second and the first contact of the third pad, respectively. The first contact of the first pad is connected to the third contact of the third pad, and the third contact of the first to the first contact of the second pad. The differential output of the Hall microsystem is the second contacts of the second and third pads as the measured magnetic field is parallel to the planes of the pads and the long sides of the contacts.

An advantage of the invention is the doubled magnetosensitivity as a result of summing the output of the Hall voltage microsystem generated by the sensors of the second and third pads with the total Hall voltage of the sensor of the first pad.

Another advantage is the simplified design of the microsystem, containing a total of nine instead of ten ohmic contacts and only three instead of six connections between them.

An advantage is the ability to fully compensate for the parasitic voltage of asymmetry

Descriptions of issued patents for inventions № 05.1 / 15.05.2020 at the output in the absence of a magnetic field (offset) using a low-resistance trimmer.

Another advantage is the increased metrological accuracy and resolution when measuring the minimum magnetic induction as a result of the high signal / noise level, due to the significant magnetic sensitivity and the trimmer-compensated parasitic offset of the output.

Explanation of the attached figure

The invention is illustrated in more detail by an embodiment thereof, given in the attached figure 1, representing the cross-section of the Hall microsystem.

Examples of the invention

The plane-magnetic-sensitive Hall microsystem contains three semiconductor pads with p-type impurity conductivity - from left to right first 1, second 2 and third 3, located parallel to each other and current source 4. On one side of each of the pads 1,2 and 3 in series and at distances from each other are formed from left to right by three rectangular ohmic contacts - the first 5, 6 and 7, the second 8, 9 and 10, and the third 11, 12 and 13, the second contacts 8, 9 and 10 are central, and the first 5, 6 and 7 and the third 11, 12 and 13 are respectively symmetrical with respect to them. One terminal of the source 4 is connected to the central contact 8 of the first pad 1, and the other to the midpoint of a low-resistance trimmer 14, the end terminals of which are connected to the third terminal 12 of the second 2 and the first terminal 7 of the third pad, respectively. 3. The first contact 5 of the first pad 1 is connected to the third pin 13 of the third pad 3, and the third pin 11 of the first 1 is connected to the first pin 6 of the second pad

2. The differential output 15 of the Hall microsystem is the second contacts 9 and 10 of the second 2 and third 3 pads, the measured magnetic field 16 being parallel to the planes of the pads 1, 2 and 3, and to the long sides of the pins 5, 6, 7, 8, 9 10, 11, 12 and 13.

The operation of the planar magnetosensitive Hall microsystem according to the invention is as follows.

When the central contact 8 is connected to one terminal of the current source 4 and the other terminal to the trimmer 14 and the contacts 7 and 12, the currents I 1 ₁₂₆ and I flow in the volumes of the three pads 1, 2 and 3. _g of contact 8 is divided into two equal and oppositely directed components I _g = I + | -I |, I = | -1 |, Figure 1. As a result of the original connection of the respective planar contacts Pi 6,5i13, in pads 2 and 3, oppositely directed current components 1 ₆ and -I flow. The trajectories of the electrons in all three substrates 1, 2 and 3 are curvilinear, because in the absence of magnetic field B 16 the planar ohmic contacts 5, 8, 11, 6, 12, 7 and 13 through which the currents flow are equipotential planes. Through these contacts, the current lines are initially directed vertically to the volume of pads 1, 2 and 3, then change their direction and in a certain section are parallel to the upper planes of pads 1,2 and 3. In general, the depth of penetration w of the currents lines at a fixed concentration of doping donor impurity N _d in n-type pads 1, 2 and 3 depends on the ratio M between the width I of contacts 8, 11,6, 12, 7 and 13, and the distances / ₂ between them, M = / y / ₂ , [4-6]. The maximum depth w at the most commonly used in microelectronics concentration of doping donor impurities N _D ~ 10 ¹⁵ cf ³ in Si is about w ~ 30 - 40 pm. Pads 2 and 3 with pins 6, 9, 12 and 7, 10 and 13, respectively, are substantially dispersed in these pads 2 and 3, a five-pin Hall microsensor in which two of the pins 12 and 7 are equivalent in purpose and function as one. At the same time, the pad 1 with contacts 5, 8 and 11 represents the well-known three-contact Hall microsensor, also known in the literature as the Rumenin microsensor, [4-6]. Its load resistors, which are usually connected to the end electrodes 5 and 11, in this case are the internal resistors R ₆₁₂ and R _? of the diffuse five-pin Hall microsensor. These resistors R ₆ and R _? determine the Hall sensor from the pad 1 operating mode generator current. Resistors R _{6 | 2} and R ₇₁₃ have the same value due to the structural symmetry in the arrangement of contacts 6, 12 and 7, 13 in structures 2 and 3. Usually the differential output 15 formed by the middle contacts 9 and 10, in the absence of external magnetic field B 16, present unrelated to the magnetic induction B 16 parasitic voltage or offset. Its compensation (reset) is done by changing the value to low

Descriptions of issued patents for inventions № 05.1 / 15.05.2020 omni trimer d 14, Figure 1. Such a possibility is absent in the known solution.

In the presence of an external magnetic field B 16 in the three-contact Hall microsensor (pad 1 with contacts 5, 8 and 11) the current I _g through contact 8 is subjected to the deflecting side effect of the Lorentz force F _L as on the end electrodes 5 and 11 generates a Hall voltage V _{H5 P} (V). Its origin is the result of the selected connection of pads 2 and 3 with pad 1, i. of resistors R ₆ and R _{7 |} of the five-contact Hall microsensor scattered in pads 2 and 3. These resistors transform the changes of the currents ΔΙ ₅ (Β) and ΔΙ _Π (Β) in the field B 16 into a Hall voltage V _{H5 P} (B). Since the ratio M is optimized to be maximal, the signal V _{H5 P} (B) is also maximal and is generated by the entire supply current I _g and not by a part of it. In the two three-contact Hall microsensors realized on pads 2 and 3, the Hall potentials V _H9 (B) on contact 9 and - V (B) on contact 10 are equal in value and have opposite sign V _H9 (B) = | - V _H10 (B). The potentials V _H5 (B) and V _H11 (B) through the circuit solution of Figure 1 change polarly the potentials of the two pads 2 and 3 - for example, one increases and the other decreases by the same value. In this way, the voltage V (B), which is equal to the value of the Hall voltage V _H910 (B) from pads 2 and 3, is added to the output signal V _H910 = V _out (B) 15 of the microsystem. Therefore, the output differential voltage V (B) 15 is doubled, i. the magnetosensitivity of the planar-magnetosensitive Hall microsystem is twice as high as the known solution. In addition, it contains nine contacts instead of ten, and there are only three connections.

The unexpected positive effect of the new technical solution lies in the original construction and the non-standard connection of the contacts 5-13,11-6i12-7 of the three structures 1, 2 and

3. Through the three-contact Hall sensor (pad 1 with contacts 5, 8 and 11), which is functionally integrated in the microsystem, the magnetic sensitivity doubles. The solution allows for complete compensation of the parasitic offset and improves the signal-to-noise ratio. At the same time, the resolution for detecting the minimum magnetic induction is increased 16.

Hall's microsystem is realized with CMOS, BiCMOS or micromachining microelectronic technologies as the three conversion zones 1, 2 and 3 represent deep p-type silicon pockets with a depth of about 7 ppm. The ohmic contacts 5, 6, 7, 8, 9, 10, 11, 12 and 13 are strongly doped n ⁺ regions formed by epitaxy and a depth of about 1 μm. The Hall microsystem can function over a wide temperature range, including in a cryogenic environment, which dramatically increases sensitivity. For even higher conversion efficiency for the purposes of low-field magnetometry, counterterrorism and navigation, pads (n-type silicon pockets) 1, 2 and 3 can be located between two identical concentrators in the B16 field of ferrite or p-metal. 2D and 3D magnetometers can be built on the basis of the new sensor solution.

Claims (1)

Patent claims 1. A plane-magnetic Hall-sensitive microsystem comprising semiconductor substrates with p-type impurity conductivity arranged parallel to each other and a current source, with an equal number of rectangles formed on one side of each of the substrates sequentially and at distances from each other. ohmic contacts - one central and the other symmetrically located relative to them, and the measured magnetic field is parallel to the planes of the pads and the long sides of the contacts, characterized by the fact that the pads are three - from left to right first (1), second 2) and third (3), as on each of them there are three contacts - first (5, 6 and 7), second (8,9 and 10), and third (11, 12 and 13), as the second contacts 8, 9 and 10) are the central, and the first (5, 6 and 7) and the third contacts (11,12 and 13) are respectively symmetrical with respect to them, and one terminal of the source (4) is connected to the central contact (8) from the first pad (1) and the other with the midpoint of a low-resistance trim p (14), the end terminals of which are connected respectively to the third contact (12) of the second pad (2) and the first contact (7) of the third pad (3), the first contact (5) of the first pad (1) with connected to the third contact (13) of the third substrate (3) and the third contact (11) of the first substrate (1) to the first contact (6) of the second substrate (2), as the differential output (15) of the Hall microsystem are the second contacts (9 and 10) of the second (2) and third (3) pad.