BG110505A - Semiconductor hall element with a parallel axis of sensitivity - Google Patents

Abstract

The semiconductor Hall element with a parallel axis of sensitivity contains a semiconductor pad (1) with an impurity type conductivity, on one side of which three rectangular ohmic contacts are formed: first (2), second (3) and third (4), located in parallel to their long sides. The first (2) and the third (4) contacts are external and the second (3) is internal. The magnetic field (8) is appliedperpendicularly to the cross-section of the pad (1). The second contact (3) and one of the external contacts (4), through respective charge resistors (5 and 6) and a voltage source (7), are connectedwith the other external contact (2). The outlet (9) is the second (3) and the external contact (4), which is connected with a charge resistor (6).

Description

ABSTRACT

HALF SEMICONDUCTOR ELEMENT WITH PARALLEL

SENSITIVITY AXIS

Sia Valcheva Lozanova

Chavdar Stanoev Rumenin

The Hall semiconductor element with a parallel axis of sensitivity comprises a semiconductor substrate (1) with impurity conductivity, on one side of which three rectangular ohmic contacts are formed, first (2), second (3) and third (4), parallel to each other. its long sides. The first (2) and third (4) contacts are terminal, and the second (3) is internal. The magnetic field (8) is applied perpendicular to the cross-section of the support (1). The second contact (3) and one of the end contacts (4) through the respective load resistors (5) and (6) and the voltage source (7) are connected to the other end contact (2). The output (9) is the second (3) and end contact (4) that is connected to the load resistor (6).

Sia Valcheva Lozanova

Chavdar Stanoev Rumenin

Sofia

HALF SEMICONDUCTOR ELEMENT WITH PARALLEL SENSITIVITY ©

TECHNICAL FIELD

The invention relates to a Hall semiconductor element with a parallel axis of sensitivity, applicable in the field of control measurement technology, low-field magnetometry, navigation, micro- and nano-sensors, automotive engineering, wireless communications, contactless automation and control, energy, positioning , regulation, medicine, military and security, and more.

BACKGROUND OF THE INVENTION

A Hall semiconductor element with a parallel axis of sensitivity is known, comprising a semiconductor substrate with a mixed type of conductivity, on one side of which is formed in series and is formed on one side. equal distances from each other three rectangular ohmic contacts, first, second and third, parallel to their long sides. The first and third contacts are terminals and are connected to both a power source in the current generator mode and to two resistors in series. The second contact is internal and output (Hall). The external magnetic field is applied perpendicular to the cross section of the semiconductor substrate and is parallel to the long sides of the rectangular ohmic contacts, the output being the Hall contact and the common point of connection of the two resistors, [1].

The disadvantage of this Hall semiconductor element with a parallel axis of sensitivity is the low magnetosensitivity, since only half of the total Hall voltage generated in this converter element can be removed from the output.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a Hall semiconductor element with a parallel axis of sensitivity with a high value of magnetic sensitivity.

This problem is solved by a Hall semiconductor element with a parallel axis of sensitivity containing a semiconductor substrate of impurity type mixed on one side of which three rectangular ohmic contacts, first, second and third, parallel to each other, are formed on one side its long sides. The first and third contacts are terminal and the second is internal. The second contact and one of the end contacts through the respective load resistors and a voltage source are connected to the other end contact. The external magnetic field is applied perpendicular to the cross-section of the semiconductor substrate and parallel to the long sides of the rectangular ohmic contacts, the output being the second and this terminal contact connected to the load resistor.

DESCRIPTION OF THE ATTACHED FIGURE

The invention is explained in more detail with the accompanying Figure, which is a cross-section of an embodiment thereof.

EXAMPLES FOR THE IMPLEMENTATION OF THE INVENTION

The Hall semiconductor element with a parallel axis of sensitivity comprises a semiconductor substrate 1 with impurity type, on one side of which three rectangular ohmic contacts are formed, first two, second 3 and third 4, arranged parallel to their long countries. The first 2 and third 4 contacts are terminal and the second 3 is internal. The second contact 3 and one of the terminal contacts 4 through the respective load resistors 5 and 6 and the voltage source 7 are connected to the other terminal contact 2. The external magnetic field 8 is applied perpendicular to the cross section of the semiconductor. : · · · · · · · · ········· • · · · · · · · · · · · · · Substrate 1 and parallel to the long sides of the rectangles ohmic contacts 2, 3, and 4, and output 9 is the second 3 and that terminal contact 4 connected to the load resistor 6.

The action of a Hall semiconductor element with a parallel axis of sensitivity according to the invention is as follows.

When the voltage source 7 is switched on, between the end (third) contact 4 with the load resistor 6 connected thereto and the other end (first) contact 2, and respectively between the second (internal) contact 3 and the end (first) contact 2 without the load resistor two alternating currents Z _{4> 2} and / ₃ , ₂ flow. Since the ohmic contacts 2, 3 and 4 are planar and represent equipotential planes, the currents through them / ₂ , / ₃ and C are initially perpendicular to the upper surface of the substrate 1 and penetrate into its volume. Then, the current trajectories become parallel to the surface of substrate 1. For example, when there is a temperature T different from the surface of the semiconductor substrate 1 from the flow of currents Z _{4; 2} and / ₃₂ ; the presence of mechanical stresses from the enclosure of the chip with the Hall element; applying insulating dielectric coatings, conductive thin layers or rails to the substrate 1 in the process; inevitable geometric lithographic errors or tolerances in the arrangement of ohmic contacts 2, 3 and 4; heterogeneities in the alloy of the pad 1; the different lengths of current paths between terminals 4 and 2, respectively 2 and 3, etc. both currents D ₂ and / ₃ , ₂ inevitably generate offset. This means that a parasitic output voltage P ₃ occurs at the output 9 between the second 3 and the terminal (third) contact 4, which is connected to the load resistor 6 in the absence of a magnetic field B 8, B = 0 _{; 4} (B = 0) ± 0. Its compensation (including reset) is easily achieved by varying the value of one of the two load resistors 5 or 6. By virtually changing the values of the two currents / _{4> 2} and / _{3 2 the} equipotential of the output contacts 3 and 4. is achieved. 5 and 6 should exceed the input impedance of semiconductors by at least one order I'm an element of Hall. Resistors 5 and 6 together with the voltage source 7 form the fixed values of the two supply currents / _{4; 2} and / _{3 2} .

The application of an external magnetic field B 8 perpendicular to the cross-section of the semiconductor substrate 1 and parallel to the long sides of the rectangular contacts 2, 3 and 4 by the Lorentz force F _L = gPa _r x B leads to deviation and deformation of the two directional currents in general. / _{4; 2} and / _{3> 2} , Kdr is the drift velocity of the carriers, q is the electron load. For example, the two current paths / _{4> 2} and / _{3> 2} , depending on the direction of the magnetic field B 8, either "shrink" to the upper surface of the substrate 1, or simultaneously "expand" inward in volume. As a result, on the upper surface of the substrate 1, where the inner ohmic contacts 3 and the third (outer) 4 are located, the magnetic field B and the currents / ₃ and C generate simultaneously two opposite Hall potentials. Furthermore, the current / _{4; 2} , in the part of its trajectory, when parallel to the surface of the substrate 1, induces an additional Hall potential in the area with the second (internal) 3 contact. Therefore, at • · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · the total Hall voltage is developed and measured

generated in the sensor, not just half of it as in the known technical solution. That is why magnetosensitivity strikes twice.

The unexpected positive effect of the new Hall element with a parallel axis of sensitivity, which doubles its magnetic sensitivity in comparison with the known one, is that at each of contacts 3 and 4 of the differential output 9 are formed in the magnetic field B 8 simultaneously by Hall potentials with opposite sign. In Hall's famous sensor, however, only one contact actually acts as Hall. In the new solution, they are two - 3 and 4. It is also unusual for the outgoing Hall contacts 3 and 4 to be adjacent to each other, contrary to the conventional practice of sensory and power contacts alternating. This circumstance also helps to develop the full Hall voltage at the output 9.

Experiments with Hall-type silicon elements with a parallel axis of sensitivity according to the invention have shown a 2-fold increase in magnetosensitivity compared to the known solution.

The preferred technology for implementing the new Hall micro converter is CMOS. The n-GaAs epitaxial technology can also be successfully used, which dramatically increases the sensitivity of the microsensor, especially for security and military purposes.

APPENDIX: one figure

REFERENCES [1] Rumenin, SV Lozanova, Hall Semiconductor Sensor, Patent Application Per. No. 109663 / 07.09.2006

Claims (1)

Patent Claims 1. A Hall semiconductor element with a parallel axis of sensitivity, comprising a semiconductor substrate of impurity type, on one side of which three rectangular ohmic contacts, first, second and third, parallel to their long sides, are formed alternately , the first and third contacts are terminal and the second is internal, with the magnetic field applied perpendicular to the cross-section of the substrate and parallel to the long sides of the rectangular ohmic contacts, characterized by that the second contact (3) and one of the end contacts (4) through the respective load resistors (5) and (6) and the voltage source (7) are connected to the other end contact (2), and the output (9) are the inner (3) and that terminal contact (4) that is connected to the load resistor (6).