阅读说明：本技术 磁场感测装置 (Magnetic field sensing device ) 是由 袁辅德 于 2019-07-24 设计创作，主要内容包括：本发明提供一种磁场感测装置,包括至少一漩涡型磁电阻及至少一磁化设定元件。漩涡型磁电阻包括钉扎层、受钉扎层、间隔层及圆形自由层。受钉扎层配置于钉扎层上,间隔层配置于受钉扎层上,而圆形自由层配置于间隔层上,且具有漩涡形磁化方向分布。磁化设定元件交替地通电与不通电,当磁化设定元件不通电时,圆形自由层的漩涡形磁化方向分布随着外在磁场而变化,以达到对外在磁场的感测。当磁化设定元件通电时,磁化设定元件所产生的磁场破坏了圆形自由层的漩涡形磁化方向分布,并使圆形自由层达到磁饱和。(The invention provides a magnetic field sensing device, which comprises at least one vortex type magneto resistor and at least one magnetization setting element. The vortex magnetoresistance includes a pinned layer, a spacer layer, and a circular free layer. The pinned layer is set on the pinned layer, the spacer layer is set on the pinned layer, and the circular free layer is set on the spacer layer and has vortex-shaped magnetization direction distribution. The magnetization setting element is alternately electrified and not electrified, and when the magnetization setting element is not electrified, the spiral magnetization direction distribution of the circular free layer changes along with the external magnetic field so as to achieve the sensing of the external magnetic field. When the magnetization setting element is energized, the magnetic field generated by the magnetization setting element destroys the distribution of the spiral magnetization directions of the circular free layer and causes the circular free layer to reach magnetic saturation.)

1. A magnetic field sensing device, comprising:

at least one vortex-type magnetoresistance, comprising:

a pinning layer;

a pinned layer disposed on the pinning layer;

a spacer layer disposed on the pinned layer; and

a circular free layer disposed on the spacer layer and having a distribution of swirl magnetization directions; and

at least one magnetization setting element, configured on one side of the vortex-type magnetoresistance, wherein the at least one magnetization setting element is alternately electrified and not electrified, and when the at least one magnetization setting element is not electrified, the vortex-shaped magnetization direction distribution of the circular free layer changes along with an external magnetic field, so as to achieve the sensing of the external magnetic field; when the at least one magnetization setting element is electrified, the magnetic field generated by the at least one magnetization setting element destroys the spiral magnetization direction distribution of the circular free layer, and the circular free layer is enabled to reach magnetic saturation.

2. The magnetic field sensing device of claim 1, further comprising:

a substrate, wherein the magnetization setting element is disposed on the substrate;

a first insulating layer covering the magnetization setting element, wherein the vortex-type magnetoresistance is disposed on the first insulating layer; and

and the second insulating layer covers the vortex-type magneto resistor.

3. The magnetic field sensing device of claim 1, further comprising:

a substrate, wherein the vortex-type magnetoresistance is disposed on the substrate;

a first insulating layer covering the vortex magnetoresistance, wherein the magnetization setting element is disposed on the first insulating layer; and

a second insulating layer covering the magnetization setting element.

4. The magnetic field sensing device according to claim 1, wherein the at least one magnetization setting element comprises a first magnetization setting element and a second magnetization setting element, the magnetic field sensing device further comprising:

a substrate, wherein the first magnetization setting element is disposed on the substrate;

a first insulating layer covering the first magnetization setting element, wherein the vortex-type magnetoresistance is disposed on the first insulating layer;

a second insulating layer covering the vortex-type magnetoresistance, wherein the second magnetization setting element is disposed on the second insulating layer; and

a third insulating layer covering the second magnetization setting element.

5. The magnetic field sensing device according to claim 1, wherein the at least one vortex-type magnetoresistance is a plurality of vortex-type magnetoresistance electrically connected as a wheatstone bridge, the wheatstone bridge outputting a differential signal corresponding to the external magnetic field when the plurality of vortex-type magnetoresistance are in a state of sensing the external magnetic field.

6. The magnetic field sensing device according to claim 5, wherein the Wheatstone bridge is electrically connected to an operator, the Wheatstone bridge outputting a null signal when the plurality of vortex magnetoresistors are in a state in which the circular free layer thereof is in magnetic saturation, the operator being configured to subtract the null signal from the differential signal corresponding to the external magnetic field to obtain a net output signal.

7. The magnetic field sensing device according to claim 5, wherein the plurality of vortex-type magnetoresistances include a first vortex-type magnetoresistance, a second vortex-type magnetoresistance, a third vortex-type magnetoresistance, and a fourth vortex-type magnetoresistance, the first vortex-type magnetoresistance is electrically connected to the third vortex-type magnetoresistance and the fourth vortex-type magnetoresistance, the second vortex-type magnetoresistance is electrically connected to the third vortex-type magnetoresistance and the fourth vortex-type magnetoresistance, a pinning direction of the first vortex-type magnetoresistance is the same as a pinning direction of the second vortex-type magnetoresistance, the pinning direction of the third vortex-type magnetoresistance is the same as a pinning direction of the fourth vortex-type magnetoresistance, and the pinning direction of the first vortex-type magnetoresistance is opposite to the pinning direction of the third vortex-type magnetoresistance.

8. The magnetic field sensing device according to claim 7, wherein a direction of a magnetic field generated at the first to fourth vortex type magnetoresistance when the at least one magnetization setting element is energized is perpendicular to a pinning direction of the first to fourth vortex type magnetoresistance.

9. The magnetic field sensing device according to claim 1, wherein the spacer layer is a non-magnetic metal layer and the swirl magnetoresistance is a giant magnetoresistance.

10. The magnetic field sensing device according to claim 1, wherein the spacer layer is an insulating layer and the vortex magnetoresistance is a tunneling magnetoresistance.

11. The magnetic field sensing device according to claim 1, wherein the at least one magnetization-setting element is a conductive sheet, coil, wire, or conductor.

Technical Field

The present invention relates to a magnetic field sensing device.

Background

Magnetic field sensors are an important component that can provide electronic compass and motion tracking for the system. In recent years, related applications have rapidly developed, particularly for portable devices. In new generation applications, high accuracy, fast response, small size, low power consumption and reliable quality have become important features of magnetic field sensors.

In a conventional giant magnetoresistance or tunneling magnetoresistance sensor, there is a structure in which a pinned layer (pinning layer), a pinned layer (pinned layer), a spacer layer (spacer layer), and a free layer (free layer) are sequentially stacked, wherein the free layer has a magnetization easy axis (magnetic easy-axis) perpendicular to a pinning direction of the pinned layer. If one wants to construct a single-axis magnetic sensor with a wheatstone bridge, multiple magnetoresistors with different pinning directions are important. For a 3-axis magnetic sensor, a plurality of magnetoresistors each having 6 pinning directions are required. However, from a manufacturing standpoint, fabricating the second pinning direction in the pinned layer in one wafer can result in a significant cost increase and can reduce the stability of the magnetization orientation configuration in the pinned layer.

In addition, flicker noise (pink noise) exists in the output signal of a typical magnetic field sensor, which affects the accuracy of the magnetic field measured by the magnetic field sensor.

Disclosure of Invention

The invention provides a magnetic field sensing device which can effectively overcome the interference of flicker noise.

An embodiment of the invention provides a magnetic field sensing device, which includes at least one vortex-type magnetoresistance (vortex magnetoresistance) and at least one magnetization setting element (magnetization setting element). The at least one vortex magnetoresistance includes a pinned layer, a spacer layer, and a circular free layer. The pinned layer is set on the pinned layer, the spacer layer is set on the pinned layer, and the circular free layer is set on the spacer layer and has vortex-shaped magnetization direction distribution. The at least one magnetization setting element is disposed on one side of the at least one vortex-type magnetoresistance, and the at least one magnetization setting element is alternately energized and de-energized, when the at least one magnetization setting element is not energized, the vortex-shaped magnetization direction distribution of the circular free layer changes with an external magnetic field, so as to achieve sensing of the external magnetic field. When the at least one magnetization setting element is energized, the magnetic field generated by the at least one magnetization setting element destroys the spiral magnetization direction distribution of the circular free layer and causes the circular free layer to reach magnetic saturation.

In an embodiment of the invention, the magnetic field sensing device further includes a substrate, a first insulating layer and a second insulating layer. The magnetization setting element is disposed on the substrate, and the first insulating layer covers the magnetization setting element, wherein the vortex-type magnetoresistance is disposed on the first insulating layer. The second insulating layer covers the vortex-type magnetoresistance.

In an embodiment of the invention, the magnetic field sensing device further includes a substrate, a first insulating layer and a second insulating layer. The vortex-type magnetoresistance is disposed on the substrate, and the first insulating layer covers the vortex-type magnetoresistance, wherein the magnetization setting element is disposed on the first insulating layer. A second insulating layer covers the magnetization setting element.

In an embodiment of the invention, the at least one magnetization setting element includes a first magnetization setting element and a second magnetization setting element, and the magnetic field sensing device further includes a substrate, a first insulating layer, a second insulating layer, and a third insulating layer. The first magnetization setting element is disposed on the substrate, and the first insulating layer covers the first magnetization setting element, wherein the vortex magnetoresistance is disposed on the first insulating layer. The second insulation layer covers the vortex magnetoresistance, wherein the second magnetization setting element is configured on the second insulation layer. A third insulating layer overlies the second magnetization setting element.

In an embodiment of the invention, the at least one vortex type magnetic resistor is a plurality of vortex type magnetic resistors electrically connected to form a wheatstone bridge. When these vortex-type magnetoresistors are in a state of sensing an external magnetic field, the wheatstone bridge outputs a differential signal corresponding to the external magnetic field.

In an embodiment of the invention, the wheatstone bridge is electrically connected to the operator. When these vortex-type magnetoresistors are in a state where their circular free layers are in magnetic saturation, the wheatstone bridge outputs a null signal. The arithmetic unit is used for subtracting the null signal from the differential signal corresponding to the external magnetic field to obtain a net output signal.

In an embodiment of the invention, the vortex magnetoresistance include a first vortex magnetoresistance, a second vortex magnetoresistance, a third vortex magnetoresistance, and a fourth vortex magnetoresistance. First vortex type magnetism resistance electric property is connected to third vortex type magnetism resistance and fourth vortex type magnetism resistance, second vortex type magnetism resistance electric property is connected to third vortex type magnetism resistance and fourth vortex type magnetism resistance, the pinning direction of first vortex type magnetism resistance is the same as the pinning direction of second vortex type magnetism resistance, the pinning direction of third vortex type magnetism resistance is the same as the pinning direction of fourth vortex type magnetism resistance, and the pinning direction of first vortex type magnetism resistance is opposite to the pinning direction of third vortex type magnetism resistance.

In an embodiment of the invention, a direction of a magnetic field generated at the first to fourth vortex magnetoresistance when the at least one magnetization setting element is energized is perpendicular to a pinning direction of the first to fourth vortex magnetoresistance.

In an embodiment of the invention, the spacer layer is a nonmagnetic metal layer, and the vortex magnetoresistance is a giant magnetoresistance.

In an embodiment of the invention, the spacer layer is an insulating layer, and the vortex magnetoresistance is a tunneling magnetoresistance.

In an embodiment of the present invention, the at least one magnetization setting element is a conductive sheet, a conductive coil, a conductive wire or a conductor.

In the magnetic field sensing device of the embodiment of the invention, since the circular free layer having the swirl magnetization direction distribution is used, the external magnetic field direction that can be sensed by the swirl magnetoresistance is less restricted. In addition, in the magnetic field sensing device according to the embodiment of the present invention, since the magnetization setting element capable of breaking the distribution of the spiral magnetization directions of the circular free layer is employed to measure the flicker noise existing in the magnetic field sensing device itself, the magnetic field sensing device according to the embodiment of the present invention can effectively overcome the interference of the flicker noise.

In order to make the aforementioned and other features and advantages of the invention more comprehensible, embodiments accompanied with figures are described in detail below.

Drawings

FIG. 1 is a cross-sectional view of a magnetic field sensing device according to an embodiment of the present invention;

FIG. 2 is a schematic top view of the vortex-type magnetoresistive and magnetization setting element of FIG. 1;

FIG. 3 is a schematic perspective view of the vortex-type magnetoresistance of FIG. 1;

FIGS. 4A to 4D respectively show the change of four magnetization direction distributions of the circular free layer in FIG. 3 by external magnetic fields in four different directions;

FIG. 5 shows the resistance value variation of the vortex-type magnetoresistance of FIG. 3 under the influence of external magnetic fields in different directions and in the absence of external magnetic fields;

FIGS. 6A to 6D show the directions of the saturation magnetization amounts generated by the vortex-type magnetoresistors of FIGS. 1 and 2 after receiving a magnetic field applied by a magnetization setting element;

FIG. 7 shows a switching curve for the vortex-type magnetoresistance of FIG. 1;

FIG. 8 is a schematic top view of a magnetic field sensing device according to an embodiment of the present invention;

FIG. 9 is a schematic waveform diagram of the output signal of the Wheatstone bridge of FIG. 8;

FIG. 10 is a cross-sectional view of a magnetic field sensing device according to another embodiment of the present invention;

fig. 11 is a schematic cross-sectional view of a magnetic field sensing device according to another embodiment of the invention.

The reference numbers illustrate:

100. 100a, 100 b: magnetic field sensing device

110: magnetization setting element

1101: first magnetization setting element

1102: second magnetization setting element

120: substrate

130: a first insulating layer

140: a second insulating layer

150: a third insulating layer

160: arithmetic unit

200: vortex type magneto resistor

210: pinning layer

220: pinned layer

230: spacer layer

240: circular free layer

D1: a first direction

D2: second direction

D3: third direction

H: external magnetic field

I: electric current

ML: direction of magnetization

P1: pinning direction

Q1, Q2, Q3, Q4: contact point

R: resistance value

R1: first vortex type magnetoresistance

R2: second vortex type magnetoresistance

R3: third vortex type magnetoresistance

R4: fourth vortex type magneto resistor

VC: center of vortex

Detailed Description

Fig. 1 is a cross-sectional schematic view of a magnetic field sensing device according to an embodiment of the invention, fig. 2 is a top view of the vortex-type magnetoresistance and magnetization setting element in fig. 1, and fig. 3 is a perspective schematic view of the vortex-type magnetoresistance in fig. 1. Referring to fig. 1 to fig. 3, a magnetic field sensing apparatus 100 of the present embodiment includes at least one vortex type magnetoresistance 200 and at least one magnetization setting element 110. The at least one vortex magnetoresistance 200 includes a pinned layer 210, a pinned layer 220, a spacer layer 230, and a circular free layer 240. The pinned layer 220 is disposed on the pinned layer 210, the spacer layer 230 is disposed on the pinned layer 220, and the circular free layer 240 is disposed on the spacer layer 230. In the present embodiment, the pinned layer 210 provides a pinning direction P1 that fixes the magnetization of the pinned layer 220 in the pinning direction P1. In the present embodiment, the material of the pinned layer 210 is an antiferromagnetic material (antiferromagnetic material), and the materials of the pinned layer 220 and the circular free layer 240 are ferromagnetic materials (ferromagnetic materials), wherein the material of the circular free layer 240 is a soft magnetic material (soft magnetic material).

In the present embodiment, the magnetic field sensing device 100 can be located in a space constructed by a first direction D1, a second direction D2 and a third direction D3, wherein the first direction D1, the second direction D2 and the third direction D3 are perpendicular to each other. In the present embodiment, the pinning direction P1 is parallel to the second direction D2, and the layers of the pinned layer 210, the pinned layer 220, the spacer layer 230, and the circular free layer 240 are parallel to the planes constructed by the first direction D1 and the second direction D2.

The circular free layer 240 has a vortex-shaped magnetization direction distribution. Specifically, in the absence of an external magnetic field, the magnetization direction ML of the circular free layer 240 is arranged in a plurality of circles along the circular contour of the circular free layer 240, and the circles are gradually reduced in diameter to finally converge to the center of the circular contour. The arrangement of the magnetization direction ML may be clockwise or counterclockwise. A vortex center VC is formed at the center of the circular free layer 240, and the magnetization direction at the vortex center VC is perpendicular to the direction of the circular free layer 240, which may be upward (i.e., toward the third direction D3 in fig. 2 and 3) or downward (i.e., toward the direction opposite to the third direction D3). At this time, the amount of magnetostatic (net magnetization) of the entire circular free layer 240 is zero.

In the present embodiment, the vortex type magnetoresistance 200 may be a Giant Magnetoresistance (GMR) or a Tunneling Magnetoresistance (TMR). When the vortex magnetoresistance 200 is giant magnetoresistance, the spacer layer 230 is a non-magnetic metal layer; when the vortex magnetoresistance 200 is a tunneling magnetoresistance, the spacer layer 230 is an insulating layer.

The at least one magnetization setting element 110 is disposed on one side of the at least one vortex magnetoresistance 200. In the present embodiment, the magnetization setting element 110 is, for example, a conductive sheet, a conductive coil, a conductive wire or a conductor, which can generate a magnetic field by passing a current to generate a magnetic field at the circular free layer 240 for setting the magnetization direction of the circular free layer 240.

The at least one magnetization setting element 110 is alternately energized and de-energized. When the at least one magnetization setting element 110 is not energized, the distribution of the spiral magnetization direction of the circular free layer 240 changes with the external magnetic field, so as to achieve the sensing of the external magnetic field. When the at least one magnetization setting element 110 is energized, the magnetic field generated by the at least one magnetization setting element 110 destroys the distribution of the spiral magnetization directions of the circular free layer 240, and causes the circular free layer 240 to be magnetically saturated.

Specifically, referring to fig. 4A, when an external magnetic field H along the first direction D1 passes through the vortex type magnetoresistance 200, the area of the vortex center VC toward the second direction D2 is increased, the area of the vortex center VC toward the opposite side of the second direction D2 is decreased, and the magnetization directions of the two areas are opposite, so that a magnetostatic quantity toward the first direction D1 is generated in the entire circular free layer 240, and the vortex center VC moves in the opposite direction of the second direction D2.

Referring to fig. 4B, when an external magnetic field H along the opposite direction of the first direction D1 passes through the vortex type magnetoresistance 200, the area of the vortex center VC toward the second direction D2 becomes smaller, the area of the vortex center VC toward the opposite direction of the second direction D2 becomes larger, and the magnetization directions of the two areas are opposite, so that a magnetostatic quantity toward the opposite direction of the first direction D1 is generated in the entire circular free layer 240, and the vortex center VC moves toward the second direction D2.

Referring to fig. 4C, when an external magnetic field H along the second direction D2 passes through the vortex type magnetoresistance 200, the area of the vortex center VC on the side facing the first direction D1 becomes smaller, the area of the vortex center VC on the side facing the opposite direction of the first direction D1 becomes larger, and the magnetization directions of the two side areas are opposite, so that a magnetostatic quantity facing the second direction D2 is generated in the entire circular free layer 240, and the vortex center VC moves toward the first direction D1.

Referring to fig. 4D, when an external magnetic field H in the opposite direction of the second direction D2 passes through the vortex type magnetoresistance 200, the area of the vortex center VC in the side facing the first direction D1 is increased, the area of the vortex center VC in the side facing the opposite direction of the first direction D1 is decreased, and the magnetization directions in the two areas are opposite, so that a magnetostatic flux is generated in the opposite direction of the second direction D2 in the entire circular free layer 240, and the vortex center VC moves in the opposite direction of the first direction D1.

Fig. 5 shows changes in resistance values of the vortex-type magnetoresistance of fig. 3 under the influence of external magnetic fields in different directions and in the absence of the external magnetic fields. Referring to fig. 3, fig. 4A to fig. 4D and fig. 5, the graph in fig. 5 shows the variation of the resistance R of the vortex magnetoresistance 200 with respect to the external magnetic field H. When the vortex magnetoresistance 200 is applied with an external magnetic field H in the same direction as the pinning direction P1, as shown in the upper left diagram of FIG. 5, the circular free layer 240 generates a net magnetization in the pinning direction P1, so that the resistance R decreases, i.e., the value of the resistance R corresponding to the black dots in the graph, as shown in FIG. 4C. When the vortex magnetoresistance 200 is applied with a magnetic field H in the opposite direction to the pinning direction P1, as shown in the bottom left diagram of FIG. 5, the circular free layer 240 generates a net magnetization in the opposite direction to the pinning direction P1, as shown in FIG. 4D, so that the resistance R rises, i.e., the value of the resistance R corresponding to the black dots in the graph. When the vortex magnetoresistance 200 is applied with an external magnetic field H perpendicular to the pinning direction P1, as shown in the upper right diagram of FIG. 5, the circular free layer 240 generates a net magnetization in the direction perpendicular to the pinning direction P1, as shown in FIG. 4A or FIG. 4B, and the orthographic projection of the net magnetization in the pinning direction P1 is zero, so that the resistance value R remains unchanged, i.e., the value of the resistance value R corresponding to the black dots in the graph. In addition, as shown in the lower right diagram of fig. 5, when the vortex magnetoresistance 200 is not applied with a magnetic field, the resistance value R remains unchanged, i.e., the value of the resistance value R corresponding to the black dots in the graph.

Fig. 6A to 6D show directions of saturation magnetization amounts generated by the eddy-type magnetoresistance of fig. 1 and 2 after receiving a magnetic field applied by a magnetization setting element. Referring to fig. 1, fig. 2 and fig. 6A, when a current I flowing in the second direction D2 is applied to the magnetization setting element 110 of fig. 1 and fig. 2, a strong magnetic field is generated at the circular free layer 240 in the first direction D1, so that the circular free layer 240 reaches magnetic saturation and a saturation magnetization is generated in the first direction D1. The circular free layer 240 forms a single magnetic domain (single domain) in which the magnetization direction of each position is directed toward the first direction D1. Since the saturation magnetization is perpendicular to the pinning direction P1 (i.e., the second direction D2), the resistance R of the vortex magnetoresistance 200 is theoretically unchanged.

Referring to fig. 1, fig. 2 and fig. 6B again, when the current I flowing in the magnetization setting element 110 of fig. 1 and fig. 2 is changed to flow in the opposite direction of the second direction D2, a strong magnetic field in the opposite direction of the first direction D1 is generated at the circular free layer 240, so that the circular free layer 240 reaches magnetic saturation, and a saturation magnetization is generated in the opposite direction of the first direction D1. The circular free layer 240 forms a single magnetic domain at this time, and the magnetization direction of each position thereof is directed in the opposite direction of the first direction D1. Since the saturation magnetization is perpendicular to the pinning direction P1 (i.e., the second direction D2), the resistance R of the vortex magnetoresistance 200 is theoretically unchanged.

Referring to fig. 1, fig. 2 and fig. 6C again, when the extending direction of the magnetization setting element 110 shown in fig. 1 and fig. 2 is changed from the original second direction D2 to the first direction D1, and the current I flows in the opposite direction of the first direction D1, a strong magnetic field is generated at the circular free layer 240 in the second direction D2, so that the circular free layer 240 reaches magnetic saturation, and a saturation magnetization is generated in the second direction D2. The circular free layer 240 forms a single magnetic domain at this time, and the magnetization direction of each position thereof is directed toward the second direction D2. Since the saturation magnetization is consistent with the pinning direction P1 (i.e., the second direction D2), the resistance R of the vortex magnetoresistance 200 is reduced to a minimum value.

Referring to fig. 1, fig. 2 and fig. 6D again, when the extending direction of the magnetization setting element 110 shown in fig. 1 and fig. 2 is changed from the original second direction D2 to the first direction D1, and the current I flows in the first direction D1, a strong magnetic field in the opposite direction to the second direction D2 is generated at the circular free layer 240, so that the circular free layer 240 reaches magnetic saturation, and a saturation magnetization is generated in the opposite direction of the second direction D2. The circular free layer 240 forms a single magnetic domain at this time, and the magnetization direction of each position thereof is directed to the opposite direction of the second direction D2. Since the saturation magnetization is opposite to the pinning direction P1 (i.e., the second direction D2), the resistance R of the spiral magnetoresistance 200 increases to a maximum value.

When the magnetization setting element 110 is not energized, the vortex type magnetoresistance 200 is in a state where the external magnetic field H can be sensed, as shown in fig. 4A to 4D, and the output signal of the vortex type magnetoresistance 200 at this time is a portion including a portion corresponding to the external magnetic field H and a portion corresponding to the flicker noise of the system. When the magnetization setting element 110 is energized to magnetically saturate the vortex magnetoresistance 200, the output signal of the vortex magnetoresistance corresponds to the flicker noise of the system. Therefore, when the magnetization setting element 110 is alternately energized and de-energized, and the output signals of the vortex magnetoresistance 200 in these two states are subtracted, the influence of the flicker noise of the system can be subtracted, and a signal corresponding to the external magnetic field H can be obtained more accurately.

In the present embodiment, the magnetic field sensing device 100 further includes a substrate 120, a first insulating layer 130 and a second insulating layer 140. The magnetization setting element 110 is disposed on the substrate 120, the first insulating layer 130 covers the magnetization setting element 110, the vortex magnetoresistance 200 is disposed on the first insulating layer 130, and the second insulating layer 140 covers the vortex magnetoresistance 200. In the present embodiment, the substrate 120 is a circuit substrate, such as a semiconductor substrate with a circuit.

Fig. 7 shows the transfer curve of the vortex-type magnetoresistance (transfer curve) of fig. 1. Referring to fig. 1, 2, 3 and 7, when a positive external magnetic field H or a negative external magnetic field H in the opposite direction of the pinning direction P1 is applied to the vortex magnetoresistance 200, the resistance R of the vortex magnetoresistance 200 increases or decreases with an increase in the absolute value of the external magnetic field H. When the intensity of the external magnetic field H increases or decreases to H_anor-H_anWhen the resistance value R of the vortex type magneto resistor 200 reaches a saturation value R + delta R_sOr R- Δ R_sAt this time, the vortex center VC disappears, and the circular free layer 240 has a single magnetic domain and its net magnetization reaches the saturation magnetization.

When the absolute value of the external magnetic field H decreases from the above saturation point (i.e. from H)_anInitially decrease or start from-H_anAt the beginning of the increase), the vortex magnetoresistance 200 continues to maintain at the saturation value(i.e., R + Δ R)_sOr R- Δ R_s) Until the absolute value of the external magnetic field H is less than H_reTime (i.e. external magnetic field less than H)_reOr greater than-H_reTime), the vortex center VC will reappear.

Thus, the vortex type magnetoresistance 200 has a first working range H_dy' can be defined as from-H_reTo + H_reAnd a second operating range may be H_dyOutside the range, i.e. less than-H_anOr greater than + H_anThe range of (1). In the first operating range, the distribution of the spiral magnetization directions of the circular free layer 240 stably exists. In the second operating range, the absolute value of the magnetic field set by the magnetization setting element 110 exceeds + H_anor-H_anWhen the circular free layer 240 becomes a single magnetic domain with a saturated net magnetization.

Fig. 8 is a schematic top view of a magnetic field sensing device according to an embodiment of the invention. Referring to fig. 1, 2, 3 and 8, in fig. 1, 2 and 3, a vortex-type magnetoresistance 200 and a magnetization setting element 110 are illustrated as an example, and in one embodiment, as shown in fig. 8, the magnetic field sensing apparatus 100 may include a plurality of vortex-type magnetoresistance 200 (e.g., 4 vortex-type magnetoresistance such as a first vortex-type magnetoresistance R1, a second vortex-type magnetoresistance R2, a third vortex-type magnetoresistance R3 and a fourth vortex-type magnetoresistance R4) and a plurality of magnetization setting elements 110 (e.g., two magnetization setting elements 110, one of the two magnetization setting elements 110 overlaps with the vortex-type magnetoresistance R1 and R3, and the other overlaps with the vortex-type magnetoresistance R2 and R4). That is, the vortex magnetoresistors 200 are electrically connected to form a wheatstone bridge, and when the vortex magnetoresistors 200 are in a state of sensing the external magnetic field (i.e. when the magnetization setting element 110 is not energized), the wheatstone bridge outputs a differential signal corresponding to the external magnetic field.

Specifically, the first vortex type magnetoresistance R1 is electrically connected to the third vortex type magnetoresistance R3 and the fourth vortex type magnetoresistance R4, and the second vortex type magnetoresistance R2 is electrically connected to the third vortex type magnetoresistance R3 and the fourth vortex type magnetoresistance R4. In addition, the pinning direction P1 of the first vortex type magnetoresistance R1 is the same as the pinning direction P1 of the second vortex type magnetoresistance R2, and both are oriented to the second direction D2. The pinning direction P1 of the third vortex type magnetoresistance R3 is the same as the pinning direction P1 of the fourth vortex type magnetoresistance R4, which are all opposite to the second direction D2. In addition, the pinning direction P1 of the first vortex magnetoresistance R1 is opposite to the pinning direction P1 of the third vortex magnetoresistance R3.

When the external magnetic field has a magnetic field component in the second direction D2, the resistance value of the first vortex magnetoresistance R1 changes by- Δ R, and the resistance value of the second vortex magnetoresistance R2 changes by- Δ R. In addition, since the pinning direction P1 of the third magnetoresistance R3 and the fourth magnetoresistance R4 is opposite to the second direction D2, the resistance value of the third magnetoresistance R3 changes by + Δ R, and the resistance value of the fourth magnetoresistance R4 changes by + Δ R. Thus, when the node Q1 receives a reference voltage VDD and the node Q2 is coupled to ground (ground), the voltage difference between the node Q3 and the node Q4 is (VDD) × (Δ R/R), which can be an output signal, and the output signal is a differential signal, wherein the magnitude of the output signal corresponds to the magnitude of the magnetic field component of the external magnetic field in the second direction D2. The node Q1 is coupled to the conductive path between the first vortex type resistor R1 and the fourth vortex type resistor R4, the node Q2 is coupled to the conductive path between the second vortex type resistor R2 and the third vortex type resistor R3, the node Q3 is coupled to the conductive path between the first vortex type resistor R1 and the third vortex type resistor R3, and the node Q4 is coupled to the conductive path between the second vortex type resistor R2 and the fourth vortex type resistor R4.

In the present embodiment, the wheatstone bridge is electrically connected to an operator 160. When the vortex magnetoresistance 200 is in the magnetic saturation state of the free layer 240, the wheatstone bridge outputs a null signal, and the operator 160 subtracts the null signal from the differential signal corresponding to the external magnetic field to obtain a net output signal, wherein the net output signal is obtained by subtracting the effect of the flicker noise, and can more accurately reflect the magnitude of the external magnetic field. In the present embodiment, when the magnetization setting element 110 is energized, the current I flows in the second direction D2, and thus the direction of the magnetic field generated at the first to fourth vortex-type magnetoresistance R1, R2, R3, and R4 thereof is perpendicular to the pinning direction P1 of the first to fourth vortex-type magnetoresistance R1, R2, R3, and R4. In this case, since the null signal includes only the flicker noise, the null signal is subtracted from the differential signal corresponding to the external magnetic field, and a net output signal that reflects the external magnetic field can be obtained. However, when the magnetization setting element 110 is disposed in such a manner that the direction of the magnetic field generated at the first to fourth vortex magnetoresistance R1, R2, R3, and R4 is parallel or antiparallel to the pinning direction P1 of the first to fourth vortex magnetoresistance R1, R2, R3, and R4, the null signal includes a saturation signal (which may be a positive value or a negative value) in addition to a portion including the flicker noise, that is, the resistance value of one portion of the first to fourth vortex magnetoresistance R1, R2, R3, and R4 increases to a maximum value, and the resistance value of the other portion increases to a minimum value. At this time, the arithmetic unit subtracts the null signal from the differential signal corresponding to the external magnetic field, and then adds or subtracts the saturation signal to obtain a net output signal accurately corresponding to the external magnetic field. In the present embodiment, the operator 160 is, for example, an arithmetic operator, which can be disposed on the substrate 120 or in the substrate 120.

Fig. 9 is a schematic waveform diagram of an output signal of the wheatstone bridge of fig. 8. Referring to fig. 8 and 9, when the wheatstone bridge is alternately switched between the sensing state (i.e. when the magnetization setting element 110 is not energized) and the null state (i.e. when the magnetization setting element 110 is energized with the current I), the voltage signal output by the wheatstone bridge in the sensing state is V_sAnd the voltage signal output by the Wheatstone bridge is V in the empty state_n. The arithmetic unit then calculates V_s-V_nTo obtain a net output signal and output it.

Fig. 10 is a schematic cross-sectional view of a magnetic field sensing device according to another embodiment of the invention. Referring to fig. 10, the magnetic field sensing device 100a of the present embodiment is similar to the magnetic field sensing device 100 of fig. 1, and the difference therebetween is as follows. In the magnetic field sensing device 100a of the present embodiment, the vortex magnetoresistance 200 is disposed on the substrate 120, and the first insulating layer 130 covers the vortex magnetoresistance 200. In addition, the magnetization setting element 110 is disposed on the first insulating layer 130, and the second insulating layer 140 covers the magnetization setting element 110. Thus, when the magnetization setting element 110 is energized with the current I, a strong magnetic field can still be generated at the vortex magnetoresistance 200.

Fig. 11 is a schematic cross-sectional view of a magnetic field sensing device according to another embodiment of the invention. Referring to fig. 10, the magnetic field sensing device 100b of the present embodiment is similar to the magnetic field sensing device 100 of fig. 1, and the difference therebetween is as follows. The at least one magnetization setting element 110 of the magnetic field sensing device 100b of the present embodiment includes a first magnetization setting element 1101 and a second magnetization setting element 1102, and the magnetic field sensing device 100b further includes a third insulating layer 150. In addition, the first magnetization setting element 1101 is disposed on the substrate 120, the first insulating layer 130 covers the first magnetization setting element 1101, the eddy type magnetoresistance 200 is disposed on the first insulating layer 130, and the second insulating layer 140 covers the eddy type magnetoresistance 200. In addition, the second magnetization setting element 1102 is disposed on the second insulating layer 140, and the third insulating layer 150 covers the second magnetization setting element 1102. Thus, when the first magnetization setting element 1101 and the second magnetization setting element 1102 are energized with the current I, a strong magnetic field can still be generated at the vortex magnetoresistance 200.

In summary, in the magnetic field sensing device according to the embodiment of the invention, since the circular free layer having the vortex-shaped magnetization direction distribution is adopted, the external magnetic field direction that can be sensed by the vortex-type magnetoresistance is less limited. In addition, in the magnetic field sensing device according to the embodiment of the present invention, since the magnetization setting element capable of breaking the distribution of the spiral magnetization directions of the circular free layer is employed to measure the flicker noise existing in the magnetic field sensing device itself, the magnetic field sensing device according to the embodiment of the present invention can effectively overcome the interference of the flicker noise.

Although the present invention has been described with reference to the above embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention.